Two spherical rain drops reach the surface of the earth with terminal velocities having ratio $16: 9$. The ratio of their surface area is

Water rises upto a height $h$ in a capillary tube on the surface of the earth. The value of $h$ will increase, if the experimental setup is kept in [ $g=$ acceleration due to gravity]

If the surface tension of a soap solution is $3 \times 10^{-2} \mathrm{~N} / \mathrm{m}$ then the work done in forming a soap film of $20 \mathrm{~cm} \times 5 \mathrm{~cm}$ will be

A large open tank containing water has two holes to its wall. A square hole of side $a$ is made at a depth $$y$$ and a circular hole of radius $$r$$ is made at a depth $$16 y$$ from the surface of water. If equal amount of water comes out through both the holes per second, then the relation between $$r$$ and $$a$$ will be