Question

A perfectly elastic ball of mass $m$ moving with velocity $u$ hits a wall moving with velocity $v$ in the opposite direction. After the collision the ball will rebound back with speed

• A. $u$
• B. $u-v$
• C. $u+2v$
• D. $u+v$

Answer 1

Answer: (C)

Correct answer is (c) $u+2v$