Two men have a weight ratio of $5 : 3$. If the ratio of the time taken by them to climb stairs is $11 : 9$,find the ratio of their power.

$A$ vehicle of mass $m$ starts from rest and accelerates. If the engine delivers a constant power $p$,what is the velocity of the vehicle at time $t$?

$A$ car of mass $1200 \,kg$ (together with the driver) is moving with a constant acceleration of $2 \,m/s^2$. How much power does the engine generate at the instant when the speed reaches $20 \,m/s$ (in $\,W$)? (Assume that the coefficient of friction between the car and the road is $0.5$ and $g = 10 \,m/s^2$).

$A$ 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

$A$ particle is moving unidirectionally on a horizontal plane under the action of a constant power supplying energy source. The displacement $(s)$ - time $(t)$ graph that describes the motion of the particle is (graphs are drawn schematically and are not to scale)

Two men with weights in the ratio $4:3$ run up a staircase in time in the ratio $12:11$. The ratio of power of the first to that of second is