Two capillary tubes A and B of the same internal diameter are kept vertically in two different liquids whose densities are in the ratio $4: 3$. If the surface tensions of these two liquids are in the ratio $6: 5$, then the ratio of rise of liquid in capillary A to that in B is (assume their angles of contact are nearly equal)
Two rain drops of same radius are falling through air each with a steady speed of $5 \mathrm{~cm} / \mathrm{s}$. If the drops coalesce, the new steady velocity of big drop will be
A capillary tube stands with its lower end dipped into liquid for which the angle of contact is $90^{\circ}$. The liquid will
A lead sphere of mass ' $m$ ' falls in viscous liquid with terminal velocity $\mathrm{V}_0$. Another lead sphere of mass ' 8 m ' but of same material will fall through the same liquid with terminal velocity