As shown in the figure,a block of mass $2 \ kg$ is released from point $P$. It slides $0.5 \ m$ on the inclined plane before hitting a spring. The spring constant is $4000 \ N/m$. The coefficient of friction between the block and the inclined plane is $0.3$. The compression in the spring will be ............... $mm$.

$A$ bullet of mass $0.01 \, kg$ travelling at a speed of $500 \, m/s$ strikes a block of mass $2 \, kg$ which is suspended by a string of length $5 \, m$. The center of gravity of the block is found to rise a vertical distance of $0.1 \, m$. What is the speed of the bullet after it emerges from the block?

$A$ body of mass $5\; kg$ is moving with a momentum of $10\; kg\; m/s$. $A$ force of $0.2\; N$ acts on it in the direction of motion of the body for $10\; s$. Find the increase in its kinetic energy. (in $; J$)

As shown below, bob $A$ of a pendulum having a massless string of length $R$ is released from $60^{\circ}$ to the vertical. It hits another bob $B$ of half the mass that is at rest on a frictionless table in the center. Assuming an elastic collision, the magnitude of the velocity of bob $A$ after the collision will be (take $g$ as acceleration due to gravity):

In the figure shown,two identical balls of mass $M$ and radius $R$ each are placed in contact with each other on a frictionless horizontal surface. $A$ third ball of mass $M$ and radius $R$ is coming down vertically and has a velocity $v_0$ when it simultaneously hits the two balls and comes to rest. Then,each of the two bigger balls will move after the collision with a speed equal to:

$A$ block of mass $m(=0.1 \ kg)$ is hanging over a frictionless light fixed pulley by an inextensible string of negligible mass. The other end of the string is pulled by a constant force $F$ in the vertically downward direction. The linear momentum of the block increases by $2 \ kg \ m/s$ in $1 \ s$ after the block starts from rest. Then,(given $g=10 \ m/s^2$):