Chapter 8 ndash Work and Chapter 8 ndash Work and EnergyEnergy

8 1 Work8 1 Work

pp 188-192pp 188-192

TERMS TO LEARNTERMS TO LEARN

Work ndash Work ndash the action that results when a the action that results when a force causes an object to move in the force causes an object to move in the direction of the force being applieddirection of the force being applied

Joule ndash Joule ndash the SI unit of workthe SI unit of work

JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE

An English An English physicistphysicist

The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim

81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance

You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter

WORKWORK

The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object

movemove in the direction of the forcein the direction of the force

ANDAND only when the force is being applied only when the force is being applied

to the objectto the object

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

TERMS TO LEARNTERMS TO LEARN

Work ndash Work ndash the action that results when a the action that results when a force causes an object to move in the force causes an object to move in the direction of the force being applieddirection of the force being applied

Joule ndash Joule ndash the SI unit of workthe SI unit of work

JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE

An English An English physicistphysicist

The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim

81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance

You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter

WORKWORK

The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object

movemove in the direction of the forcein the direction of the force

ANDAND only when the force is being applied only when the force is being applied

to the objectto the object

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE

An English An English physicistphysicist

The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim

81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance

You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter

WORKWORK

The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object

movemove in the direction of the forcein the direction of the force

ANDAND only when the force is being applied only when the force is being applied

to the objectto the object

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance

You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter

WORKWORK

The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object

movemove in the direction of the forcein the direction of the force

ANDAND only when the force is being applied only when the force is being applied

to the objectto the object

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

WORKWORK

The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object

movemove in the direction of the forcein the direction of the force

ANDAND only when the force is being applied only when the force is being applied

to the objectto the object

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

CALCULATING WORKCALCULATING WORK

The equation you use to calculate The equation you use to calculate work iswork is

work = force work = force times distancetimes distance

W = F times dW = F times d

The SI unit of work is the The SI unit of work is the joule (J)joule (J)

1 J = 1 N 1 J = 1 N m m

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 Work

W = F x dDistance (m)

Force (N)

Work (joules)

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work and energy81 Work and energy

You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy

Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force

Solving ProblemsSolving Problems

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

11 Looking forLooking for helliphellipwork done by personwork done by person

22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m

33 Relationships Relationships Work = force x distanceWork = force x distance

44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules

Solving ProblemsSolving Problems

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork

81 Work81 Work

Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork