A bullet of mass m moving with velocity v strikes a block of mass M at rest and gets embedded into it. The kinetic energy of the composite block will be
By conservation of momentum, mv + M(o) = (m+M) v Velocity of composite block $ V = \left ( { m \over m+M} \right) v $ K.E. of composite block = $ { 1 \over 2} (M+ m)v^2 $