The figure shows the vertical cross-section of a vessel filled with a liquid of density $\rho$. The normal thrust per unit area on the walls of the vessel at the point $P$,as shown,will be

The pressure at the bottom of a tank containing a liquid does not depend on

$A$ submarine has a window of area $30 \times 30 \,cm^2$ on its ceiling and is at a depth of $100 \,m$ below sea level. If the pressure inside the submarine is maintained at the sea-level atmospheric pressure,then the force acting on the window is ............. $N$ (consider density of sea water $\rho = 1.03 \times 10^3 \,kg/m^3$,acceleration due to gravity $g = 10 \,m/s^2$).

During blood transfusion,the needle is inserted into a vein where the gauge pressure is $2000 \; Pa$. At what height (in $m$) must the blood container be placed so that blood may just enter the vein? (Density of whole blood,$\rho = 1.06 \times 10^{3} \; kg \; m^{-3}$,$g = 9.8 \; m \; s^{-2}$)

Explain why you cannot make a decent cup of tea on a mountain.

From the adjacent figure,the correct observation is: