The upper half of an inclined plane of inclination $$\theta $$ is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by

Three blocks with masses m, 2m and 3m are connected by strings, as shown in the figure. After an upward force F is applied on block m, the masses move upwards at constant speed v. What is the net force on the block of mass 2m ? (g is the acceleration due to gravity)

A stone is dropped from a height h. It hits the ground with a certain momentum P. If the same stone is dropped from a height 100% more than the previous height, the momentum when it hits the ground will change by

A conveyor belt is moving at a constant speed of 2 ms^$$-$$1. A box is gently dropped on it. The coefficient of friction between them is $$\mu $$ = 0.5. The distance that the box will move relativce to belt before coming to rest on it, taking g = 10 m s^$$-$$2,, is