Question

A man of 60 kg is running on the road and suddenly jumps into a stationary trolly car of mass 120 kg. Then. the trolly car starts moving with velocity 2 ms^–1 . The velocity of the running man was ______ ms^–1 . when he jumps into the car.

Answer 1

Correct answer is 6 m/s

Taking the system as man and trolley and using conservation of linear momentum.

60 x v = (60 + 120) × 2 

⇒ v = 6 m/s