Energy in Collision

Q. In an inelastic collision of two bodies, the final kinetic energy is less than the initial kinetic energy of the system.

1. False
2. True

Q. A ball of mass $4\text{kg}$ moving with velocity $4\text{m/s}$ collides with another identical ball at rest. The kinetic energy of the balls after collision is $\frac{7}{8}$ times of the original. Find the coefficient of restituton $\left(e\right)$.

1. $1$
2. $0.866$
3. $0.732$
4. $0.239$

Q. A ball of mass $4\text{kg}$ moving with velocity $4\text{m/s}$ collides with another identical ball at rest. The kinetic energy of the balls after collision is $\frac{7}{8}$ times of the original. Find the coefficient of restituton $\left(e\right)$.

1. $1$
2. $0.866$
3. $0.732$
4. $0.239$

Q. The total energy of a system is always conserved irrespective of whether external forces act on the system.

1. False
2. True

Q. A particle of mass $m$ is moving with speed $2v$ and collides with a mass $2\text{m}$ moving with speed $v$ in the same direction. After collision, the first mass is stopped completely while the second one splits into two particles each of mass $m$, which move at angle ${45}^{\circ }$ with respect to the original direction.
The speed of each of the moving particle will be

1. $\sqrt{2}v$
2. $\frac{v}{\sqrt{2}}$
3. $\frac{v}{\left(2\sqrt{2}\right)}$
4. $2\sqrt{2}v$

Q. Two balls $A$ and $B$ of masses $2\text{kg}$ each are moving with speeds $1\text{m/s}$ and $2\text{m/s}$ on a frictionless surface. After colliding, ball $A$ returns back with speed $0.5\text{m/s}$, then the maximum potential energy of deformation is

1. $45\text{J}$
2. $24\text{J}$
3. $4.5\text{J}$
4. $2.4\text{J}$