A glass rod of radius '$$r_1$$' is inserted symmetrically into a vertical capillary tube of radius '$$r_2$$' ($$r_1 < \mathrm{r}_2$$) such that their lower ends are at same level. The arrangement is dipped in water. The height to which water will rise into the tube will be ($$\rho=$$ density of water, T = surface tension in water, g = acceleration due to gravity)

An ice cube of edge $$1 \mathrm{~cm}$$ melts in a gravity free container. The approximate surface area of water formed is (water is in the form of spherical drop)

Water rises upto a height of $$4 \mathrm{~cm}$$ in a capillary tube. The lower end of the capillary tube is at a depth of $$8 \mathrm{~cm}$$ below the water level. The mouth pressure required to blow an air bubble at the lower end of the capillary will be '$$\mathrm{X}$$' $$\mathrm{cm}$$ of water, where $$\mathrm{X}$$ is equal to

The speed of a ball of radius $$2 \mathrm{~cm}$$ in a viscous liquid is $$20 \mathrm{~cm} / \mathrm{s}$$. What will be the speed of a ball of radius $$1 \mathrm{~cm}$$ in same liquid?