$A$ body starts moving unidirectionally under the influence of a source of constant power. Which one of the graphs correctly shows the variation of displacement $(s)$ with time $(t)$?

An athlete throws a shotput of mass $25 \,kg$ with an initial speed of $4 \,ms^{-1}$ at an angle of $45^{\circ}$ with the horizontal from a height of $2 \,m$ above the ground. Assuming air resistance to be negligible,the kinetic energy of the shotput when it just touches the ground is . . . . . . $\left(g=10 \,ms^{-2}\right)$ (in $\,J$)

If a lighter body (mass $M_1$ and velocity $V_1$) and a heavier body (mass $M_2$ and velocity $V_2$) have the same kinetic energy,then

$A$ motor drives a body along a straight line with a constant force. The power $P$ developed by the motor must vary with time $t$ according to

Explain oblique collision.

State whether the following statements are true or false:
$(a)$ If $\overrightarrow P \cdot \overrightarrow Q = 0$,then the angle between $\overrightarrow P$ and $\overrightarrow Q$ is $0^o$.
$(b)$ If two bodies stick together after a collision,the collision is called an elastic collision.
$(c)$ When an equal force is applied to a heavy and a light object on the same surface,more work is done by the force on the heavy object.