Water flows through a frictionless duct with a cross-section varying as shown in the figure. Pressure $p$ at points along the axis is represented by:

$A$ cylindrical vessel partially filled with water is rotated about its vertical central axis. Its surface will

The shown $H$-shaped apparatus contains an ideal incompressible liquid and has dimensions as shown in the figure. The diameters of the tubes are small compared to $h$ and $R$. The apparatus is rotated with a constant angular velocity $\omega$ about a symmetric vertical axis as shown in the figure. The pressure at point $A$ is

Liquid and gas both are fluids; distinguish between them and state which property is common between them.

$A$ pump is used to deliver water at a certain rate through a pipe. To obtain $n$ times the water in the same time,by what factor should the velocity of water,the force of water,and the power of the pump be increased?

When an air bubble of radius $r$ rises from the bottom to the surface of a lake,its radius becomes $\frac{5r}{4}$. Taking the atmospheric pressure to be equal to $10 \ m$ height of water column,the depth of the lake would approximately be ....... $m$ (ignore the surface tension and the effect of temperature).