A homogeneous solid cylinder of length $L(L < H/2)$, cross-sectional area $A/5$ is immersed such that it floats with its axis vertical at the liquid-liquid interface with length $L/4$ in the denser liquid as shown in the figure. The lower density liquid is open to atmosphere having pressure $P_0$. Then, density $D$ of solid is given by

A spherical drop of water has $1\, mm$ radius. If the surface tension of water is $70\times10^{-3}\, N/m$ . Then the difference of pressures between inside and outside of the spherical drop is :

A wax candle floats vertically in a liquid of density twice that of wax. The candle burns at the rate of $4\  cm/hr$ . Then, with respect to the surface of the liquid the upper end of the candle will 

Water falls from a tap, down the streamline

What is the pressure on a swimmer $20 \,m$ below the surface of water is ..... $atm$

Water drop whose radius is $0.0015\, mm$ is falling through the air. If the coefficient of viscosity of air is $1.8 \times 10^{-5}\, kg/m-s$, then assuming buoyancy force as negligible the terminal velocity of the dorp will be