Question

Determine the coefficient of restitution e between ball A and ball B the velocities of A and B before and after collision are shown. A=8m/s moving forward and B=2m/s moving backward before collision and A=1m/s moving forward and B=9m/s moving forward after collision.

Answer 1

According to question

before collision

speed of ball A, say u₁=8m/s

speed of ball B, say u₂=2m/s

After collision

speed of ball A, say v₁₌1m/s

speed of ball B,say v₂=9m/s

cofficient of restitution say e,

e=$\frac {v_{2}-v_{1}}{u_{1}-(-u_{2})}$

= $\frac {9-1}{8-(-2)}$ { u₂ is negative because initially ball is moving backwards}

= $\frac {8}{10}$

=0.8

Therefore the cofficient of restitution is 0.8