Question Detail
Question
A large mass explodes into two smaller masses. Mass m moves to the right at speed v. Mass M moves to the left at speed V. Find the speed V of mass M.
Correct Answer
Option B is the correct answer.
Detailed Explanation
Conservation of momentum: initial momentum = 0. So 0 = m v - M V (taking right as positive). Thus M V = m v => V = (m/M) v.
Hint
Use conservation of momentum. The total momentum before explosion is zero.