Question

A metal ball of mass 2 kg moving with speed of 36 km/h has a head on collision with a stationary ball of mass 3 kg. If after collision, both the balls move as a single mass, then the loss in K.E. due to collision is

(a) 100 J

(b) 140 J

(c) 40 J

(d) 60 J

Answer 1

Correct option (d) 60 J

Explanation:

 Mass of metal ball = 2 kg;

Speed of metal ball (v₁) = 36 km/h = 10 m/s and mass of stationary ball = 3 kg.

Applying law of conservation of momentum,