Two blocks, with masses $m_1=2.5 \mathrm{kg}$ and $m_2=14 \mathrm{kg}$, approach each other along a horizontal, frictionless track. The initial velocities of the blocks are $v_1=12.0 \mathrm{m} {\mathrm{s}}^{-1}$ to the right and $v_2=3.4 \mathrm{m} {\mathrm{s}}^{-1}$ to the left. The two blocks then collide and stick together. Which of the graphs could represent the force of block $1$ on block $2$ during the collision?

A small puck is sliding to the right with momentum ${\overrightarrow{p}}_i$ on a horizontal, frictionless surface, as shown in figure. A force is applied to the puck for a short time and its momentum afterward is ${\overrightarrow{p}}_f$. Which lettered arrow shows the direction of the impulse that was delivered to the puck?

A moving $2 \mathrm{kg}$ ball with a speed of $2 \mathrm{m} {\mathrm{s}}^{-1}$ hits obliquely a stationary identical ball inelastically as shown. If the first ball move away with angle $\alpha =30°$ to the original path, find the total kinetic energy lost after the collision:-

Find the distance between centre of gravity and centre of mass of a two particle system attached to the ends of a light rod. Each particle has the same mass. Length of the rod is $R$, where $\mathrm{R}$ is the radius of the Earth.

In an experiment with a beam balance an unknown mass $m$ is balanced by two known masses of $16\mathrm{kg}$ and $4\mathrm{kg}$ as shown in figure. The value of the unknown mass $m$ is :-

A uniform $"L"$ shaped rigid body $AOB$ of mass $m,$ where $AO=OB=l$ and $\angle AOB$ is a right angle, is hinged to a smooth joint at point $A$ of the body and can swing freely in a vertical plane. Initially, the body is released from rest with $AB$ horizontal. Find the maximum kinetic energy of the body.