Question

A light body and a heavy body have same momentum. Which has a greater kinetic energy.

Answer 1

Let mass of lighter body be m (velocity =v) and heavier body be M(velocity =V)

Then, as per question mv=MV

Now Kinetic Energy of lighter block =$\frac{m{v}^2}{2}$

Kinetic Energy of heavier block = $\frac{M{V}^2}{2}$

Thus K.E. of lighter block : K.E. of heavier block =v:V=M:m>1

Thus lighter block have more kinetic energy.