An automobile of mass m accelerates, starting from rest, with the engine supplying constant power 'P'. How the velocity of the automobile vary with time?
As Fv=P=constant
i.e.mdvdtv=P[As F=mdvdt]or ∫ vdv=∫pmdt
By integrating both sides we get v22=pmt+C1
As initially the body is at rest i.e.v=0 at t=0,so C1=0 ∴v=(2ptm)12