What is the relation obeyed by the angles of contact $$\theta_1, \theta_2$$ and $$\theta_3$$ of 3 liquids of different densities $$P_1, P_2$$ and $$P_3$$ respectively $$(\mathrm{P}_1 < \mathrm{P}_2 < \mathrm{P}_3$$) when they rise to the same capillary height in 3 identical capillaries and having nearly same surface tension $$\mathrm{T}$$ ?

Water flows from a tap with steady flow, through a cross sectional area of $$10^{-3} \mathrm{~m}^2$$ with a speed of $$0.5 \mathrm{~ms}^{-1}$$. Assume the pressure is constant throughout the stream of water. The cross sectional area of the stream $$0.19 \mathrm{~m}$$ below the tap is

Modulus of rigidity of an incompressible liquid is

64 rain drops of the same radius are falling through air with a steady velocity of $$0.5 \mathrm{~cm} \mathrm{~s}^{-1}$$. If the drops coalesce, the terminal velocity would be