# Physics trolley investigation

Essay by jimbarson February 2004

Physics Trolley Investigation

I will be finding out the affect of change in height of a ramp on the velocity of the trolley dropped from the ramp.

Variables

1.Mass and shape of trolley.

2.Height of the ramp.

3.Force with which the trolley is dropped.

4.Position on the ramp that the speed of the trolley is taken

5.Length of ramp

6.Surface of the ramp and the trolleys wheels

Key Variables

Output variable - Speed of the trolley

Key Input variable - Height of the ramp

Prediction

I predict that as the height of the ramp increases so will the velocity of the trolley. I think this because at the top of the ramp the trolley will have its greatest gravitational potential energy (GPE) this is because it is at its highest point. If GPE = mass x gravity x height then its greatest GPE will be at its highest point as it is the only variable we will change, mass will stay the same.

At the bottom it will have its greatest kinetic energy. This is because the gravitational potential energy (GPE) gradually turns into kinetic energy (KE) as it falls. This happens because energy cannot be created of destroyed, it can just be changed into other forms of energy. Therefore maximum GPE = Maximum KE, so mgh = ÃÂ½ mv2. However, due to friction the equation should really be mgh = ÃÂ½ mv2 + energy lost due to friction, this is more correct as it accounts for the energy lost due to friction. If we divide this equation by mass then we are left with gh = ÃÂ½ v2, if we then multiply both sides by 2 we have 2gh = v2. This means that V2 = 2gh, this makes height and velocity...