The block of mass `M` moving on the frictionless horizontal surface collides with the spring constant `k` and compresses it by length `L` . The maximum momention of the block after collision is

Answer

D

Explanation

When block of mass M collides with the spring, its kinetic energy gets converted into elastic potential energy of the spring. From the law of conservation of energy. `1/2 Mv^2 = 1/2 KL^2 :." " v = sqrt(K/M) L`
Where v is the velocity of block by which it collides with spring.
So, its maximum momentum, `P = Mv = M sqrt(K/M) L = sqrt(M K) L`
After collision, the block will rebound with same linear momentum.