A car of mass `m` starta from rest and accelerates so that the instyantaneous power delivered to the car has a constant magnitude `P_(0)`. The instaneous velocity of this car is proportional to

Answer

B

Explanation

Constant power of car, ` P_0 = F xx v`
` = ma xx v = m (dv)/(dt) xx v`
or ` P_0 dt = mv dv` ltbr. Integratignboth sides, we get
` int_0^t P_o dt = int _0^v mv d v = ( mv^2 /2 , i.e. , P_0 t =( mv^2)/2`
` v= sqrt ( 2 P_0 t)/m` or ` v prop sqrt t` .