$A$ book is lying on the table. What is the angle between the action of the book on the table and the reaction of the table on the book ............ $^o$

$A$ spherical body of mass $100 \,g$ is dropped from a height of $10 \,m$ from the ground. After hitting the ground, the body rebounds to a height of $5 \,m$. The impulse of force imparted by the ground to the body is given by: (given $g = 9.8 \,m/s^2$)

If the speed of an object is doubled,then which of the following is true?

$A$ ball of mass $0.15 \, kg$ is dropped from a height $10 \, m$,strikes the ground,and rebounds to the same height. The magnitude of the impulse imparted to the ball is $(g = 10 \, m/s^2)$ nearly: (in $kg \cdot m/s$)

$A$ ping-pong ball of mass $m$ is floating in air by a jet of water emerging out of a nozzle. If the water strikes the ping-pong ball with a speed $v$ and just after collision the water falls dead,the rate of flow (in $kg/s$) of water in the nozzle is equal to

$A$ particle moves in the $x-y$ plane under the influence of a force $\vec{F}$ such that its linear momentum is $\vec{P}(t) = \hat{i} \cos(kt) - \hat{j} \sin(kt)$. If $k$ is a constant,the angle between $\vec{F}$ and $\vec{P}$ will be: