# Coefficient of Restitution?

#### BMcN

Whats the equation for the coefficient of restitution again? Went blank!

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#### lavalamp

Code:
Coefficient of Restitution = Speed of Separation = v[sub]1[/sub]-v[sub]2[/sub]
-------------------   -----
Speed of Approach    u[sub]1[/sub]-u[sub]2[/sub]

#### Doc Al

Mentor
For the simple case of something bouncing off the floor (or any immoveable object) the coefficient of restitution is:

c = vf/v0
where v0 is the speed of the object before the collision, and vf is the speed after the collision.

For perfectly elastic collisions, c = 1.

#### lavalamp

It's like waiting for a bus, you have to wait for ages and then two come along at once.

#### BMcN

v1-v2/u1-u2, thats the one, thats guys!

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