Question

A highly elastic ball moving at a speed of `3 m//s` approaches a wall moving towards it with a speed of `3 m//s`. After the collision. the speed of the ball will be

A. `3m//s`
B. `6m//s`
C. `9m//s`
D. zero

Answer 1

Correct Answer - C
For elastic collision `e=1`. let speed of the ball be `v` towards left after collision then w.r.t wall, incident velocity `=` reflected velocity. We get `3+3=v-3impliesv=9m//s`