A man of mass $M$ standing on a frictionless surface throws a ball of mass $m$ with a velocity $v$ at an angle $heta$ with the horizontal. The velocity of the man after he throws the ball is:

A block of mass m is placed on a smooth inclined plane of inclination θ with the horizontal. The force exerted by the plane on the block has a magnitude

A boy of weight 20 kg slides down a rope hanging from the branch of tree. If the force of friction against him is 40 N; then acceleration of the boy will be

Two blocks of masses ${m_1} = 4$ kg and ${m_2} = 2$ kg are connected to the ends of a string which passes over a massless, frictionless pulley. The total downwards thrust on the pulley is nearly

Two masses ${m_1} = 5\;kg\,and\,{m_2} = 4.8\;kg$ tied to a string are hanging over a light frictionless pulley. What is the acceleration of the masses when they are free to move $(g = 9.8\;m/{s^2})$

An 80 kg person is parachuting and is experiencing a downward acceleration of $\;2.8{\rm{m}}{{\rm{s}}^{ - 2}}$. The mass of the parachute is 5 kg. The upward force on the open parachute is (Take $g = 9.8{\rm{m}}{{\rm{s}}^{ - 2}})$

A gun of mass 5 kg fires a bullet of mass 50 g with a velocity of 200 m/s. What is the recoil velocity of the gun?

A partly hanging uniform chain of length chain of length L is resting on a rough horizontal table. $l$ is the maximum possible length that can hang in equilibrium. The coefficient of friction between the chain and table is

A body weight 8 g when placed in one pan and 18 g when placed on the other pan of a false balance. If the beam is horizontal when both the pans are empty. The true weight of the body is

A man slides down on a telegraphic pole with acceleration equal to one-fourth of acceleration due to gravity. The frictional force between man and pole is equal to in terms of man's weight w

A shell initially at rest explodes into two pieces of equal mass, then the two pieces will