A body of mass 2 kg makes an elastic collision with another body at rest and continues to move in the original direction with one-fourth its original speed. The mass of the second body which collides with the first body is

Step-by-step solution

Conservation of linear momentum gives aligned & m₁ u₁+m₂ u₂ & =m₁ v₁+m₂ v₂ & m₂ v₂ aligned = 3 u 2 ...(i) Conservation of kinetic energy gives aligned & 1 2 m₁ u₁^2+ 1 2 m₂ u₂^2 & 1 2 m₁ v₁^2+ 1 2 m₂ v₂^2 m₂ v₂^2 & = 15 u^2 8 ...(ii) aligned Hence, on solving Eqs. (i) and (ii), we get m₂=1.2 ~kg