Power is the rate of work. Therefore Power= Work/Time
In this question we are provided with the force 100N and the Power 450W.
Power is a function of velocity.
work done=force×distance
Power=Work/Time=(force×distance)/time
The part distance/time gives velocity
Therefore power= force×velocity
Substituting for the values in the above formula:
450W=100N×velocity
Velocity=450W/100N
Velocity=4.5ms⁻¹
