Force & MovementForce & Movement

D. Crowley, 2008D. Crowley, 2008

Force & MovementForce & Movement To be able to explain how the force behind an object

affects its movement

To be able to explain how the force behind an object affects its movement

AccelerationAcceleration If both of these vehicles had exactly the same size engine, which

would reach 60 first?

If both of these vehicles had exactly the same size engine, which would reach 60 first?

versus

Mass >3000kg Mass 1200kg

The smaller mini would get to 60 before the large range rover as it has a much smaller mass - if the engine is the same, then the force pushing it forward is the same, so a smaller mass would equal faster acceleration

Acceleration = Force Mass

The smaller mini would get to 60 before the large range rover as it has a much smaller mass - if the engine is the same, then the force pushing it forward is the same, so a smaller mass would equal faster acceleration

Acceleration = Force Mass

AccelerationAcceleration Draw force arrows needed for each car to accelerate them both

at the same rate

Draw force arrows needed for each car to accelerate them both at the same rate

versus

As the range rover is almost 3x as heavy as the mini, the force needed to accelerate it at the same rate as the mini needs to be 3x as big

This is why the force arrow for the range rover is so much bigger (and why in real life, it has a much more powerful engine)

As the range rover is almost 3x as heavy as the mini, the force needed to accelerate it at the same rate as the mini needs to be 3x as big

This is why the force arrow for the range rover is so much bigger (and why in real life, it has a much more powerful engine)

Force ExperimentForce Experiment How could you investigate how changing the force behind an

object will affect how far it moves

Apparatus at your disposal include: - Rubber bands Force meters String Meter rulers Stop watches Ramps Margarine tubs Plasticine Sellotape

How could you investigate how changing the force behind an object will affect how far it moves

Apparatus at your disposal include: - Rubber bands Force meters String Meter rulers Stop watches Ramps Margarine tubs Plasticine Sellotape

Force ExperimentForce Experiment Remember, whatever plan you have chosen to follow, you must

only change 1 independent variable (the force applied)

Every other variable must be kept constant (i.e. the mass of the margarine tub, the slope it must travel across etc…)

You may have decided to see how different forces affect the distance traveled by a margarine tub containing a given mass of plasticine - you will need to measure how far the tub traveled when different forces (at least 5 different forces) were applied, repeating each experiment at least 3x

Remember, whatever plan you have chosen to follow, you must only change 1 independent variable (the force applied)

Every other variable must be kept constant (i.e. the mass of the margarine tub, the slope it must travel across etc…)

You may have decided to see how different forces affect the distance traveled by a margarine tub containing a given mass of plasticine - you will need to measure how far the tub traveled when different forces (at least 5 different forces) were applied, repeating each experiment at least 3x

Start point End point

Force10N15N20N

Etc…

Distance traveled

ResultsResultsForce

(N)

Distance traveled by object (cm)

Measurement 1 Measurement 2 Measurement 3 Average

10

15

20

25

30

ConclusionConclusion Analyses your results, and conclude your findings

Evaluate your experiment, and then suggest improvements…

Hopefully you found that as the force increased, the distance traveled by the object increased

Analyses your results, and conclude your findings

Evaluate your experiment, and then suggest improvements…

Hopefully you found that as the force increased, the distance traveled by the object increased

As the force increased, whilst frictional forces remained fairly static (although there would be slightly more friction with the heavier mass)

As the force increased, whilst frictional forces remained fairly static (although there would be slightly more friction with the heavier mass)