Question

How do you calculate the coefficient of restitution?

Answer 1

The coefficient of restitution often denoted `e` can be found with some notion of Newton's Experimental Law.

This law states that: "in a system of colliding bodies(usually 2 bodies) the relative velocity of separation is directly proportional to the relative velocity of approach".

Mathematically expressed, `V_A-V_B alpha U_A-U_B`
`or V_B-V_A alpha U_B-U_A`
For a system of colliding bodies `"A"` and `"B"`

The constant of proportionality is `-e`
Thus we have,

`V_A-V_B =-e (U_A-U_B)`

`=> e=-(V_A-V_B)/( U_A-U_B )`

Thus, all you need to calculate e are the respective initial and final velocities of the two bodies involved in collision.