If a force $F$ is applied on a body and it moves with a velocity $v$,the power will be

$A$ $10 \text{ H.P.}$ motor pumps out water from a well of depth $20 \text{ m}$ and fills a water tank of volume $22380 \text{ litres}$ at a height of $10 \text{ m}$ from the ground. The running time of the motor to fill the empty water tank is ........... $\text{minutes}$ $(g = 10 \text{ m s}^{-2})$

$A$ quarter horsepower motor runs at a speed of $600 \text{ r.p.m.}$ Assuming $40\%$ efficiency,the work done by the motor in one rotation will be:

$A$ force acts on a body of mass $15 \,kg$, initially at rest. If the instantaneous power due to the force at the end of the third second is $5 \,W$, then the instantaneous power (in $W$) at the end of the $4 \,s$ will be

The average work done by a human heart while it beats once is $0.5 \, J$. Calculate the power used by the heart if it beats $72$ times in a minute.

An elevator in a building can carry a maximum of $10$ persons,with the average mass of each person being $68 \; kg$. The mass of the elevator itself is $920 \; kg$ and it moves with a constant speed of $3 \; m/s$. The frictional force opposing the motion is $6000 \; N$. If the elevator is moving up with its full capacity,the power delivered by the motor to the elevator $\left(g = 10 \; m/s^{2}\right)$ must be at least .............. $W$.