Question

A car moving at a velocity of 120m/s pass a stationary police patrol car parked behind the billboard. If the patrol car begins to chase the moving car, how far will it take overtake the moving car and what time?

Answer 1

It depends on the acceleration a of the police car. For the violator and the policeman, we have

$$d=vt,\\\space\\ t=\sqrt{2d/a}.\\\space\\ t=\sqrt{2vt/a},\\\space\\ t=2v/a.$$