Force, mass and acceleration required practical

This practical investigates how two factors effect acceleration. The mass of an object or the force of an object. Examiners might show you either situation. You will need to carefully look at the question to check which is being investigated. The most common examples are using a trolley rolling down a ramp, but it could also be a glider on an air track or any other object.

Investigating the effect of mass is easier, you can simply add more mass to the trolley. Investigating the force is harder, you can not simply push the trolley harder as this will not be consistent and so not VALID.

Typical variables

• Independent - Changing either the mass by adding masses or force by adding masses to a pulley. The masses on the pulley pull the trolley down the ramp with a constant force. Watch out, both situations use masses.

• Dependent - You are measuring acceleration, but to do this you need to first measure the speed at one point and the speed at another point. You would use light gates to do this.

• Control variables - this could be what ever you are not changing and the surface, angle of ramp, trolley etc.

Key formula

Every physics practical has a formula to include. This one is Acceleration = Change in velocity / Time taken

And Force = Mass x Acceleration