A U tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of 10 mm above the water level on the other side. Meanwhile the water rises by 65 mm from its original level (see diagram). The density of the oil is

The bulk modulus of a spherical object is 'B'. If it is subjected to uniform pressure 'P', the fractional decrease in radius is

Three liquids of densities $$\rho $$₁, $$\rho $$₂  and $$\rho $$₃ (with $$\rho $$₁ > $$\rho $$₂ > $$\rho $$₃), having the same value of surface tension T, rise to the same height in three identical capillaries. The angles of contact $$\theta $$₁, $$\theta $$₂ and $$\theta $$₃ obey

A rectangular film of liquid is extended from (4 cm $$ \times $$ 2 cm) to (5 cm $$ \times $$ 4 cm). If the work done is 3 $$ \times $$ 10^$$-$$4 J, the value of the surface tension of the liquid is