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Iraq moves to defuse war momentum
Storm Gains Momentum But Not Power In Trek Across Gulf
Group hopes to gain Momentum with improv events
Push For FDA Regulation Of Tobacco Gains Momentum In Congres S
MINI Maintains Winning Momentum
Passenger rail projects are gaining momentum
Fumbled punt turns momentum You have the momentum the critical need is that you use that momentum and bury them in this third quarter
Unit ThreeChapter 7 ndash Momentum
Chapter 8 ndash Energy
Momentuminertia in motion
mass in motion
The momentum of an object is equal to the mass of the object times the velocity of the object
Momentum = mass velocity
p = m v
The equation illustrates that momentum is directly
proportional to an objects mass and directly proportional to the
objects velocity
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Unit ThreeChapter 7 ndash Momentum
Chapter 8 ndash Energy
Momentuminertia in motion
mass in motion
The momentum of an object is equal to the mass of the object times the velocity of the object
Momentum = mass velocity
p = m v
The equation illustrates that momentum is directly
proportional to an objects mass and directly proportional to the
objects velocity
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Momentuminertia in motion
mass in motion
The momentum of an object is equal to the mass of the object times the velocity of the object
Momentum = mass velocity
p = m v
The equation illustrates that momentum is directly
proportional to an objects mass and directly proportional to the
objects velocity
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The momentum of an object is equal to the mass of the object times the velocity of the object
Momentum = mass velocity
p = m v
The equation illustrates that momentum is directly
proportional to an objects mass and directly proportional to the
objects velocity
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The equation illustrates that momentum is directly
proportional to an objects mass and directly proportional to the
objects velocity
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The standard metric unit of momentum is the kgms
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Momentum is a vector quantity
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
A large truck has more momentum then a small car
going the same speed
Why
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
But a small car going very fast can have a greater momentum then a large truck going very
slow
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
If the momentum of an object changes either the mass or velocity or sometimes both
changed Mass usually stays the same so the velocity is
usually what changes
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
And if velocity changes acceleration occurs
What causes acceleration
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
FORCEThe greater the force acting on
the object the greater the change in velocity and therefore the greater momentum change
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
How long the force acts upon an object is important
Brief time brief force small change
Same force over an extended period of time greater change
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Sohelliphelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Both force and time are important in changing
momentum
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The quantity Force x time interval
is call impulse
Impulse = F x t
(Units ndash N s)
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Impulse = change in momentum
sohelliphellip
F x t = Δ(m x v)
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Increasing Momentum
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
When hitting a baseball or golf ball you want to hit with a large
force for a long time So you want an impact force to be
great Thatrsquos why your coaches always yell at you to
ldquofollow throughrdquo
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Decreasing Momentum
To stop a car you can hit a concrete wall or a haystack You will be decreased by the same impulse whichever you choose
Which one do you want Why
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
(Overhead)
The same impulse does not mean the same amount of force or the same amount of time It
means the same product of force and time
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
By hitting the haystack the impact time (the time during which your momentum is brought to zero) is extended A longer impact time decreases the force of the impact and decreases the deceleration
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
More examples
When you catch a baseball with your bare hand do you just catch it or do you give a little
when you catch it
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
When you jump off of something do you land stiff legged or do
you bend your knees
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Air bags in carshellipextend the time required to stop the momentum of the driver and
passenger and therefore decrease the force
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
a Boxer moves away from the punch increases time of impact
reduces force of impactb When boxer moves toward the punch time of impact is reduced Force of impact is increased
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Bouncing
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Impulses are greater when objects bounce
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The impulse required to bring an object to a stop and then to
ldquothrow it back againrdquois greater than the impulse required to merely bring the
object to a stop
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
If a flower pot falls on your head you may be in trouble If it
bounces you might be in serious trouble Why
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Conservation of Momentum
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Newtonrsquos Second Law says
To accelerate an object a net force must be applied
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
For MomentumTo change the momentum of an
object exert an impulse on it
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Either the force or impulse has to come from outside the object
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Pushing on the dashboard of your car does not change the
momentum of the car(internal force)
A push on the outside of your car could change the momentum of the car
(external force)
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
If no external force or impulse is applied then there can be no
change in momentum
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Againhelliphelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Momentum is a vector meaning it has magnitude and
direction
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
So because momentum is a vector it can be canceled out or
brought to equilibrium
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Canon ndash Cannonball system
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
The canon fires the cannon ball The force on the cannonball is equal to the force pushing back on the canon (3rd law) so the net force is zero If no net force or net impulse acts on a system the momentum of that system
does not change
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Conservedwhen momentum or any other
quantity does not change
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Law of Conservation of Momentum
In the absence of an external force the momentum of a
system remains unchanged
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Collisions
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Net Momentumbefore equals Net Momentumafter
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Elastic CollisionsWhen objects collide without being permanently deformed and without generating heat
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Inelastic Collisions
When colliding objects become tangled or crumpled and
generate heat
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
You decidehellipElastic or Inelastic
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Net (mass)(Velocity)Before = Net (mass)(velocity)After
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Friction at the point of impact is negligible so it is not taken into
account
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
Friction produces an impulse to decrease momentum after a
collisionhelliphellip
