Force and Motion

Objective: determine how force affects the motion of an object

Force & Motion 9-11-12

• Focus Question: What happens to an object when an unbalanced force acts upon it?

• Prediction:

• Procedure: Follow the directions

• Data

Force and Motion

1. What is force?

2. How does force affect the motion of an object?

3. What is net force?

4. How does a balanced force affect the motion of an object?

5. How does an unbalanced force affect the motion of an object?

Net Force is the overall force acting on an object. For example, if there is a 10N force acting upwards, and a 5N force acting downwards, then the net force is 5N upwards. A Force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. An example of Force is a cart being pulled up a hill.

Calculate the net force of each object.Determine if the force is balanced or unbalanced and describe the affect on the motion of the object.

6.

7.

200 N 200 N

200 N 400 N

Calculate the net force of each object.Determine if the force is balanced or unbalanced and describe the affect on the motion of the object.

8.

9.

800 N 200 N

200 N400 N

800 N

Calculate the net force of each object.Determine if the force is balanced or unbalanced and describe the affect on the motion of the object.

10.

11.

800 N1000

N

200 N 400 N

800 N1000

N

speed: how fast something is going

speed = distance time

s = dt

remember speed is measured in our cars in miles per hours (per means divide)

12) JJ runs 24 miles in three hours. What is his speed?

BE SURE TO INCLUDE UNITS!!!

Velocity is speed with direction….

Are each of the following speed or velocity?

13) Quansha driving her low-rider Impala 30 miles per hour is ______….

14) Claire driving her low-rider Impala 30 mph south on Kuykendahl is _______!

15) Colby is driving his Ferrari 120 miles per hour north on I-45. Speed or velocity?

Energy Types….

electrical

chemical

kinetic(mechanical)

lightheat

potential (kinetic)

potential (chemical)sound

mechanical/kinetic – energy of motion

potential (kinetic) – the ability to release energy due to an object’s location

chemical – energy released bybreaking the bonds in compounds

potential (chemical) – energy storedin the chemical bonds of compounds

sound – energy traveling in wavesor vibrations through the air

electrical – energy created by movingelectrons

light – energy from the movementof electromagnetic waves

heat – energy given off as thermalradiation

List the energy transformations for the following:

16) flashlight

17) toaster oven

Movement of heat energy……

convection: movement of energyby the mass movement of particles(like hot air rises!)

conduction: transfer of energy fromparticle to particle.

radiation: movement of energy by electromagnetic waves (light)

18) What type of heat transfer is beingdescribed when the fireman tells Morganto touch the door to see if it is hot beforeopening it (but not the door knob)?

Conduction, convection or radiation???

19) What type of heat transfer is beingdescribed when Colton lays in the sunand works on his tan?

Conduction, convection or radiation???

20) What type of heat transfer is beingdescribed: Jay visits “Balloons Over Houston” and watch the hot air balloons float away?

Conduction, convection or radiation???

21) What type of heat transfer is beingdescribed: Megan enjoys warming herhands up by the campfire on a coldwinter night.

Conduction, convection or radiation???

Newton’s 3 Laws….

First Law: An object in motionwill remain in motion…an object atrest will remain at rest…unless actedupon by an unbalanced force.

second law: the acceleration of an object is directly proportional tothe force acting on it and inverselyproportional to its mass

in other words: F = ma

where F is forcem is massa is acceleration

third law: for every action, there isan equal and opposite reaction.

aka: action/reaction

Which Law is described by the following:

22) Winston notices it is easier to pushhis ’69 Mustang than his ‘012 SUV

Which Law is described by the following:

23) Ximena is driving her snowmobile;she hits a patch of ice and skids througha turn.

Which Law is described by the following:

24) A bullet hurts a lot more when it is shot out of a gun rather than thrownat you!

Which Law is described by the following:

25) A rocket shoots up in the air by“whooshing” massive amounts of exhaust downwards.

simple machines…..

simple machines…..

wheel & axlewedgepulleyleverincline planescrew

simple machines do NOT changethe amount of work….

they either reduce the input forceor change the direction of the force needed.

If the force is reduced, the distanceof the effort is increased!