$A$ container of height $10 \, cm$ is filled with water. There is a hole at the bottom. Find the pressure difference between points at the top and the bottom.

$A$ barometer tube reads $76 \ cm$ of mercury. If the tube is gradually inclined at an angle of $60^\circ$ with the vertical,keeping the open end immersed in the mercury reservoir,the length of the mercury column will be ........ $cm$.

Why does an air bubble formed in water grow in size as it rises from the bottom to the surface? Explain.

$A$ barometer kept in a stationary elevator reads $76 \ cm$. If the elevator starts accelerating upwards,the reading will be:

Why is mercury used in a barometer?

$A$ manometer reads the pressure of a gas in an enclosure as shown in the figure. The absolute and gauge pressure of the gas in $cm$ of mercury are (Take atmospheric pressure $= 76\,cm$ of mercury)