A railroad car of mass M is at rest on frictionless rails when a man of mass m strts moving on the car towards the engine. If the car recoils with a speed v backward on the rails, with what velocity is the man aproaching the engine?

Answer

A

Explanation

A railrod car of ma sM is at rest o frictionless rails when a man of mass m starts movng on the casr towards the engine. The car recoils with a speed v backward on the rails.
Let the mass moving with a velocity x w.r.t the engine.
`:.` The velocity of the mass w.r.t earth is (x-v) towards right.
`V_(CM)=0(Initially at rest)`
`:.-0=-Mv+m(x-v)`
`rarr Mv=m(x-v)`
`rarr mx=Mv+mv`
`rarr x=((M+m)/m)v`
`=(1+M/m)v`