The figure shows two containers $P$ and $Q$ with the same base area $A$,each filled to the same height with the same liquid. Select the correct alternative.

The height to which a cylindrical vessel must be filled with a homogeneous liquid,such that the average force with which the liquid presses the side of the vessel is equal to the force exerted by the liquid on the bottom of the vessel,is equal to:

Why is mercury used in a barometer?

$A$ swimming pool has a depth of $3 \,m$. The pressure at the bottom of the pool due to water alone is: (Density of water is $1000 \,kg \,m^{-3}$, Acceleration due to gravity $= 10 \,m \,s^{-2}$)

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

The density of the liquid filled in the container is $900 \ kg/m^{3}$. Calculate the force exerted on the bottom of the container. (Given: $g = 10 \ m/s^{2}$) (in $N$)