# Homework Help: Calculate elasticity of collision from kinetic energy loss?

1. Nov 30, 2014

### Sewager

1. The problem statement, all variables and given/known data
After a lot of searching I can't seem to find a way to solve this. Basically, for a bouncing ball, if I know the dropped height and rebound height in a vacuum. How do I calculate the elasticity between the ball and the floor?

2. Relevant equations
K = 1/2 mv2

3. The attempt at a solution
I did a lot of searching online...but I still have no idea. I tried to calculate kinetic energy loss, but what's after that?

2. Nov 30, 2014

### Sewager

Any help is appreciated, thank you!

3. Nov 30, 2014

### haruspex

What definition do you have for elasticity?

4. Nov 30, 2014

### Sewager

5. Nov 30, 2014

### haruspex

That doesn't define elasticity. You need a definition to have any hope of answering the question.
The concept of a coefficient of elasticity arises in many diverse subjects. In collisions, the more usual term is the coefficient of restitution: http://en.wikipedia.org/wiki/Coefficient_of_restitution. See if that helps.

6. Nov 30, 2014

### Sewager

Ah, this is exactly what I m looking for, thank you so much!