$A$ motor boat is travelling with a speed of $3.0\, m/s$. If the force on it due to water flow is $500\, N$,the power of the boat is

$A$ pump is used to deliver water at a certain rate from a given pipe. To obtain $n$ times the water in the same time from the same pipe,by what factor should the power of the motor be increased?

$A$ body is moving unidirectionally under the influence of a source of constant power. Its displacement in time $t$ is proportional to

$A$ car of mass $m$ moving with velocity $u$ on a straight road in a straight line, doubles its velocity in time $t$. The power delivered by the engine of the car for doubling the velocity is

$A$ particle moves with a velocity $\vec{v} = 5\hat{i} - 3\hat{j} + 6\hat{k} \text{ m/s}$ under the influence of a constant force $\vec{F} = 10\hat{i} + 10\hat{j} + 20\hat{k} \text{ N}$. The instantaneous power will be ............... $\text{J/s}$.

$A$ quarter horsepower motor runs at a speed of $600 \ rpm$. Assuming $60 \%$ efficiency,the work done by the motor in one rotation is (in $J$)