$A$ 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:

The unit of power is

$A$ body moves along a straight line under the action of a constant power delivered by an engine. The distance covered by the body in time $t$ is proportional to:

$A$ 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?

Two bodies of mass $m_1$ and $m_2$ $(m_2 > m_1)$ are connected by a light inextensible string which passes through a smooth fixed pulley. The instantaneous power delivered by an external agent to pull $m_1$ with constant velocity $v$ is

At any instant of time $t$, the displacement of a particle is given by $x = 2t - 1$ ($SI$ units) under the influence of a force of $5 \,N$. The value of instantaneous power is (in $SI$ units):