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 boat carrying a number of large stones is floating in a water tank. What would happen to the water level if a few stones are unloaded into water

Two equal drops are falling through air with a steady velocity of $5 \,cm / second$. If two drops coalesce, then new terminal velocity will be ......... $cm / s$

Two equal drops are falling through air with a steady velocity of $5\, cm/second$. If two drops coalesce to form one drop then new terminal velocity will be

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 wooden cube first floats inside water when a $200\,g$ mass is placed on it. When the mass is removed the cube is $2\,cm$ above water level. The side of cube is ......... $cm$