If $$S$$ is stress and $$Y$$ is young's modulus of material of a wire, the energy stored in the wire per unit volume is

A $$20$$ $$cm$$ long capillary tube is dipped in water. The water rises up to $$8$$ $$cm.$$ If the entire arrangement is put in a freely falling elevator the length of water column in the capillary tube will be

A wire fixed at the upper end stretches by length $$l$$ by applying a force $$F.$$ The work done in stretching is

If two soap bubbles of different radii are connected by a tube