# GPE to KE for a ramp

1. Apr 10, 2010

### TerryB

Ok now my problem is this- Ignoring resistances (I'm factoring these in later), if a ball rolls down a ramp the initial GPE energy goes to KE.

So the equation would be mgh=(1/2)mv*2 so mass cancels out leaving gh=(1/2)v*2
multiply by two gives 2gh=v*2.

So I have plotted a graph of change in height by Velocity and resulted in a straight line graph. I'd have thought this was wrong as by the equation above the change in height is proportional to velocity squared so should it not be a curve?

There's probably something completely stupid I'm doing but I've been doing Physics for 6 days straight so my mind's gone blank.

Any help is much appreciated

2. Apr 10, 2010

### rcgldr

I'm not sure what language you used, but usually v*2 means v times 2, multiply, not exponentiate. If you're using a spreadsheet, it should have some type of power() function.

3. Apr 10, 2010

### TerryB

Oops my bad!! As I said I'm tired :p I meant to say v^2

And I've done it by hand but its still a straight line. I have a feeling its because the curve is rather shallow so it is hard to see it on my graph.

Last edited: Apr 10, 2010