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?

Water rises to a height of $$2 \mathrm{~cm}$$ in a capillary tube. If cross-sectional area of the tube is reduced to $$\frac{1}{16}^{\text {th }}$$ of initial area then water will rise to a height of

Work done in increasing the size of a soap bubble from radius of $$3 \mathrm{~cm}$$ to $$5 \mathrm{~cm}$$ in millijoule is nearly (surface tension of soap solution $$=0.03 \mathrm{~Nm}^{-1}$$)