In a capillary tube of area of cross-section 'a' water rises to height ' $h$ '. To what height will water rise in a capillary tube of area of cross-section $4 a$ ?

The velocity of small spherical ball of mass ' $m$ ' and density ' $\mathrm{d}_1$ ', when dropped in a container filled with glycerine becomes constant after some time. The viscous force acting on the ball if density of glycerine is ' $\mathrm{d}_2$ ' is

A solid cylinder of length $l$ and cross-sectional area $\frac{a}{5}$ 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 figure. The lower density liquid ( $\rho$ ) is open to atmosphere having pressure $\mathrm{P}_0$. The density d of solid cylinder is

The amount of work done in blowing a soap bubble such that its diameter increases from $\mathrm{d}_1$ to $\mathrm{d}_2$ is ( $\mathrm{T}=$ surface tension of soap solution)