Question

. Two masses m and 2m are dropped from certain height h. then on reaching the
ground
(a) K.E of them will be equal (b) K.E of the heavier is 4 times the K.E of the lighter
(c) K.E of lighter is 4 times the K.E of the heavier
(d) K.E of the heavier is more than that of the lighter.

Answer 1

Since the free falling acceleration is not dependent on mass, the final velocities of the both masses are same.

The kinetic energy

$${\rm KE}=\frac{mv^2}{2}$$

Hence, the kinetic energy of the heavier mass is two times of kinetic energy of lighter. Answer (d).