Work, Energy an...

An engine pumps up 100 kg of water through a height of 10 m in 5s. given that the efficiency of the engine is 60%. If g = m/sec², the power of the engine is

The power of pump, which can pump 200 kg water to a height of 50 m in 10 sec, will be

An engine pump is used to pump a liquid of density ρ continuously through a pipe of cross-sectional area A. If the speed of flow of the liquid in the pipe is v, then the rate at which kinetic energy is being imparted to the liquid is

An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of 2 m/s. The mass per unit length of water in the pipe is 100 kg/m. What is the power of the engine

A particle of mass M starting from rest undergoes uniform acceleration. If the speed acquired in time T is V, the power delivered to the particle is

A body projected vertically from the earth reaches a height equal to earth\'s radius before returning to the earth. The power exerted by the gravitational force is greatest

A mass m slips along the wall of a semispherical surface of radius R. The velocity at the bottom of the surface is

A ball is projected vertically upwards with a certain initial speed. Another ball of the same mass is projected at an angle of 60° with the vertical with the same initial speed. At highest points of their journey, the ratio of their potential energies will be

The kinetic energy possessed by a body of mass m moving with a velocity v is equal to 1/2 mv², provided

A bullet of mass 0.02 kg travelling horizontally with velocity 250 ms^–1 strikes a block of wood of mass 0.23 kg which rests on a rough horizontal surface. After the impact, the block and bullet move together and come to rest after travelling a distance of 40 m. The coefficient of sliding friction of the rough surface is (g = 9.8 ms^–2)