Question

Consider a child playing with a toy car of mass M. The car is moving with velocity v. A stream of water is then shot towards the car. All the water shot at the car is captured and
stored in a small tanker at the back of the car at the rate dm/dt. The water has velocity
u before it hits, and comes to rest (with respect to the car) after hitting. What force must
the child apply to the car to keep it moving with velocity v?

Answer 1

this is a momentum problem