Two closed containers of equal weight and size are to be dipped into water up to the same depth. There is a hole at the bottom of one of the containers through which water can enter it. For which container, more work has to be done?

In a cistern there is water up to a depth of 1.2 m. There is a circular hole of diameter 1 cm at the bottom of the cistern. To stop the flow of water through this hole, what force should be applied on the hole?

The water level in a tank is 5m high. There is a hole of 1cm^2 cross section at the bottom of the tank through which water is licking. Find out the initial rate of leakage of water in metre^3//sec unit. (Take g=10m//sec^2 )

Two containers A and B have the same volume. Container A contains 5 moles of O_2 gas. Container B contains 3 moles of He and 2 moles of N_2 . Both the containers are separately kept in vacuum at the same temperature. Both the containers have very small orifices of the same area through which the gases leak out. Compare the rate of effusion of O_2 with that of He gas mixture.

A tank contains water up to a height H. A hole is made at a depth h from the upper surface. The horizontal range of the jet of water coming out from the hole is

A cylindrical container is to be made from certain solid material which the following constraints : It has a fixed inner volume of V mm^3 , has a 2 mm thick solid wall and is open at the top. The bottom of the container is a solid circular disc of thickness 2 mm and is of radius equal to the outer radius of the container. If the volume of the materia! used to make the container is minimum when the inner radius of the container is 10 mm, then the value of V/(250pi) is

A source of light is placed at the bottom of a tank filled with water up to the height of 80 cm. Calculate the area at the surface of water through which light rays will be emitted. Refractive index of water = 1.33.