Two identical particles are moving with same velocity $v$ as shown in figure. If the collision is completely inelastic then
The velocity of separation is zero
The velocity of approach is $2\,v \sin\, (\theta /2)$
The common velocity after collision is $v \cos\,(\theta /2)$
All of the above
How much work does a pulling force of $40\, N$ do on the $20\, kg$ box in pulling it $8\, m$ across the smooth floor at a constant speed. The pulling force is directed at $60^o$ above the horizontal .............. $\mathrm{J}$
If the momentum of a body increases by $0.01\%$, its kinetic energy will increase by ........... $\%$
State if each of the following statements is true or false. Give reasons for your answer.
$(a)$ In an elastic collision of two bodies, the momentum and energy of each body is conserved.
$(b)$ Total energy of a system is always conserved, no matter what internal and external forces on the body are present.
$(c)$ Work done in the motion of a body over a closed loop is zero for every force in nature.
$(d)$ In an inelastic collision, the final kinetic energy is always less than the initial kinetic energy of the system.
Figure shows the vertical section of frictionless surface. $A$ block of mass $2\, kg$ is released from the position $A$ ; its $KE$ as it reaches the position $C$ is ................ $\mathrm{J}$
In the figure shown the potential energy $(U)$ of a particle is plotted against its position $'x'$ from origin. The particle at