$A$ $2 \ kg$ object is initially at rest. It is acted upon by a force as indicated in the figure. Find the total work done by the force in $3 \ s$. (in $J$)

An object of mass $m \, kg$ with speed $v \, m/s$ strikes a wall at an angle $\theta$ with the normal and rebounds at the same speed and same angle. The magnitude of the change in momentum of the object will be

In projectile motion,two particles of masses $m_1$ and $m_2$ have velocities $\vec{V}_1$ and $\vec{V}_2$ respectively at time $t=0$. Their velocities become $\vec{V}_1^{\prime}$ and $\vec{V}_2^{\prime}$ at time $2t$ while still moving in air. The value of $[(m_1 \vec{V}_1^{\prime} + m_2 \vec{V}_2^{\prime}) - (m_1 \vec{V}_1 + m_2 \vec{V}_2)]$ is ($g =$ acceleration due to gravity).

$A$ $140\, g$ ball,in horizontal flight with a speed $v_1$ of $39.0\, m/s$,is struck by a bat. After leaving the bat,the ball travels in the opposite direction with speed $v_2 = 39.0\, m/s$. If the impact time $\Delta t$ for the ball-bat collision is $1.20\, ms$,what average net force acts on the ball? (in $N$)

In the figure given below,the position-time graph of a particle of mass $0.1 \,kg$ is shown. The impulse at $t = 2 \,s$ is .......... $kg \,m \,s^{-1}$.

$A$ block of mass $2 \ kg$ is free to move along the $x$-axis. It is at rest and from $t=0$ onwards it is subjected to a time-dependent force $F(t)$ in the $x$ direction. The force $F(t)$ varies with $t$ as shown in the figure. The kinetic energy of the block after $4.5 \ s$ is (in $J$)