Two bodies of equal mass moving in opposite directions at equal speeds collide and stick. Afterwards:

  1. momentum doubles
  2. they move at the same speed
  3. kinetic energy is unchanged
  4. they are at rest and all kinetic energy is lost
Answer

D) they are at rest and all kinetic energy is lost

Total momentum was zero, so final velocity is zero. SLO P-11-B-13 · Application

Physics MCQ · More Momentum and Collisions MCQs · Practise