Question

An open water tight railway wagon of mass 5 × 10³ kg coasts at an initial velocity 1.2 m/s without friction on a railway track. Raindrops fall vertically down wards into the wagon. The velocity of the wagon after it has collected 10³ kg of water will be

(A) 0.5 m/s 

(B) 2 m/s 

(C) 1 m/s 

(D) 1.5 m/s

Answer 1

Correct option: (C) 1 m/s

Explanation:

Applying conservation principle of momentum,