$A$ body of mass $m$ kg is lifted by a man to a height of one metre in $30\, s$. Another man lifts the same mass to the same height in $60\, s$. The work done by them are in the ratio:

$A$ string is used to pull a block of mass $m$ vertically up by a distance $h$ at a constant acceleration $\frac{g}{3}$. The work done by the tension in the string is ..............

$A$ man of mass $50 \ kg$ carrying a load of $10 \ kg$ reaches the top of a building in $4 \ minutes$. The work done by the man is $6 \times 10^4 \ J$. If he reaches the top in $2 \ minutes$,the work done by the man will be:

The kinetic energy acquired by a body of mass $m$ traveling a distance $s$,starting from rest under the action of a constant force,is directly proportional to:

$A$ body of mass $10 \ kg$ moves a distance of $10 \ m$ with a constant velocity up a smooth inclined plane of angle $\theta = 30^\circ$. Calculate the work done by the external applied force acting parallel to the plane in $J$. $[g = 10 \ m/s^2]$

$A$ force of $4 \,N$ acts on a $10 \,kg$ body initially at rest. Let $W_1$ be the work done by the force during $0 \leq t \leq 1 \,s$. Likewise, $W_2$ is the work done by the force during $1 \,s \leq t \leq 2 \,s$, where $t$ is time in seconds. The ratio $\frac{W_2}{W_1}$ is