$A$ force of $(2\hat{i} + 3\hat{j} + 4\hat{k})\,N$ acts on a body for $4\,s$ and produces a displacement of $(3\hat{i} + 4\hat{j} + 5\hat{k})\,m$. The power used is :- ............... $W$ (in $.5$)

An electric motor produces a tension of $9000 \ N$ on a reel containing an electric cable at a rate of $2 \ ms^{-1}$. Calculate the power of the electric motor in $kW$.

$A$ vehicle of mass $m$ starts from rest and accelerates. If the engine delivers a constant power $P$,then the position $s$ of the vehicle at time $t$ is given by:

$A$ car of mass $m$ is driven with acceleration $a$ along a straight level road against a constant external resistive force $R$. When the velocity of the car is $V$,the rate at which the engine of the car is doing work will be

The average power required to lift a $100 \ kg$ mass through a height of $50 \ m$ in approximately $50 \ s$ would be ............. $J/s$.

Water falls from a height of $60\, m$ at the rate of $15\, kg/s$ to operate a turbine. The losses due to frictional forces are $10\%$ of energy. How much power is generated by the turbine ............. $kW$ ? $(g = 10\, m/s^2)$