A girl of mass `40kg` jumps with a horizontal velocity of `5m//s` onto a stationary cart with frictionless wheels. The mass of the cart is `3kg`. What is her velocity as the cart starts moving? Assume that there is no external unbalanced force working in the horizontal direction.

A girl of mass `40kg` jumps with a horizontal velocity of `5m//s` onto

1.	A girl of mass `40kg` jumps with a horizontal velocity of `5m//s` onto a stationary cart with frictionless wheels. The mass of the cart is `3kg`. What is her velocity as the cart starts moving? Assume that there is no external unbalanced force working in the horizontal direction.
Answer» Here, `m_(1)= 40kg, u_(1)=5m//s` , `m_(2)= 3kg, u_(2)=0` If `v` is velocity of the girl on the cart, then applying principle of conservation of linear momentum, we get `(m_(1)+m_(2))v = m_(1)u_(1)+m_(2)u_(2)` or `(40+3)v = 40xx5+0= 200` or `v=(200)/(43)= 4.65m//s`