Question

A man weighing 60 kg runs along the rail with a velocity of 18 km/hr and jumps into a car of mass 1 quintal standing on the rail . calculate the velocity with which car will start travelling along the rail

Answer 1

Mass of the man(M) = 60 kg
Mass of the rail(m) = 1000 kg
Initial velocity of the man(U) = 18 km/h = 5 m/s
Initial velocity of the rail(u) = 0 m/s
Final velocity of the man(V) = 0 m/s
Final velocity of the rail(v) = ?

By the law of conservation of linear momentum, we have
MU + mu = MV + mv
If u and V are 0,
MU = mv
= v = MU/m
= (60 × 18)/1000
= 1.08 m/s