$A$ car of mass $m$ is driven with acceleration $a$ along a straight road against a constant external resistance $R$. When the velocity is $v$,the power of the engine is

$A$ man riding a bicycle moves at a speed of $7.2 \ km/hr$ up an incline having a length of $20 \ m$ and a height of $1 \ m$. The total mass of the man and the bicycle is $100 \ kg$. What is the power of the man in $W$?

$A$ car of mass $m$ is accelerating on a level smooth road under the action of a single force $F$. The power delivered to the car is constant and equal to $P$. If the velocity of the car at an instant is $v$,then after travelling how much distance does its velocity become double?

$A$ body of mass $2 \,kg$ starts from rest and moves with uniform acceleration. It acquires a velocity $20 \,ms^{-1}$ in $4 \,s$. The power exerted on the body in $2 \,s$ in watts is

An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of $2\, m/s$. The mass per unit length of water in the pipe is $100\, kg/m$. Calculate the power $W$ of the engine. (in $, W$)

If the heart pumps $1 \ cc$ of blood in $1 \ s$ at a pressure of $20000 \ N/m^2$,find the power of the heart in $W$.