Atmospheric Pressure and Gauge Pressure

The pressure at the bottom of a tank of water is $3\mathrm{P}$ where $\mathrm{P}$ is the atmospheric pressure. If the water is drawn out till the level of water is lowered by one-fifth, the pressure at the bottom of the tank will now be

A piston of mass M = 3kg and radius R = 4cm has a hole into which a thin pipe of radius r = 1cm is inserted. The piston can enter a cylinder tightly and without friction, and initially it is at the bottom of the cylinder. 750gm of water is now poured into the pipe so that the piston & pipe are lifted up as shown. Find the height H of water in the cylinder h of water in the pipe

An open U-tube contains mercury. When $13.6 \mathrm{cm}$ of water is poured into one of the arms of the tube, then the mercury rise in the other arm from its initial level is

A manometer reads the pressure of a gas in an enclosure as shown in figure. The absolute and gauge pressure of the gas (in $cm$ of mercury) in the enclosure is

(Take atmospheric pressure =$76 \mathrm{cm}$ of $Hg$)

 A vessel filled with a liquid of density $\rho$falls vertically downwards with an acceleration $a(<g)$. The gauge pressure $P$ at depth $h$ below the free surface of liquid is :
 

The height of the mercury column in a simple barometer is h. As the tube is inclined with the vertical at an angle $\alpha$, the length of the mercury column along the length of the tube will become 

A manometer tube contains a liquid of density $3\times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$. When connected to a vessel containing a gas, the liquid level in the other arm of the tube is higher by $10 \mathrm{cm}$. When connected to another sample of enclosed gas, the liquid level in the other arm of the manometer tube falls $7 \mathrm{cm}$ below the liquid level in the first arm. Which of the two samples exerts more pressure and by what amount?

The height of mercury column in a simple barometer is $h$. As the tube is inclined with the vertical at an angle $\alpha$, then length of mercury column along the length of the tube will become

Assuming the density of air to be $1.295 \mathrm{kg} {\mathrm{m}}^{-3}$, find the fall in barometric height of mm of Hg at a height of $107 \mathrm{m}$ above sea level. Take density of mercury $13.6\times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$.

Calculate the barometer reading at a place where atmospheric pressure is $0.98 \mathrm{bar}$. Given that the density of mercury is $13.6\times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$.

Water of density $\rho$ in a clean aquarium forms a meniscus, as illustrated in the figure. Calculate the difference in height $h$ between the centre and the edge of the meniscus. The surface tension of water is $\gamma$.

A $\mathrm{U}$-tube of uniform cross-section initially contained a liquid of density $2\rho$ and had a length of $L$ in the tube. Now another liquid (immiscible with the previous liquid) of density $\rho$ is poured in the $U$ tube from one end such that this liquid also fills length $L$ in the tube. Find the difference in the levels of the liquid on the two sides of the tubery

A mercury barometer has a cylindrical capillary tube of radius $\mathrm{r}=\sqrt{2} \mathrm{mm}$ inverted vertically on the mercury in the trough. Atmospheric pressure is $76 \mathrm{cm}$ of mercury but the level of mercury in the capillary is $75 \mathrm{cm}$. The portion of the tube without mercury is $10 \mathrm{cm}$ in length. Considering that this region is occupied by ideal gasses, the number of moles of the ideal gas will be : (Given: Temperature $=37°\mathrm{C}$)

Two vertical conducting cylinders $A$ and $B$ of different cross sections are connected by a thin tube as shown. An ideal gas is trapped in the cylinders by two airtight pistons of masses $1.0\mathrm{kg}$ and $2.0\mathrm{kg}$ respectively. Initially the pistons are at the same height $40\mathrm{cm}$ above the base of the cylinders. If an additional mass of $10\mathrm{g}$ were gently placed on the piston in the cylinder $A$, Which of the following statements correctly describe the new steady state ultimately reached.

An amount of water is poured on top circular face of a horizontal glass cylinder. Excess amount of water spills over the edges and a little amount of water remains there in a thin uniform layer, a portion of which is shown in the figure. If contact angle is $\mathrm{\theta }$ and surface tension of water is $\mathrm{\sigma }$, the vertical thickness of the water layer far away the edge is $\mathrm{t}$. the point in the plane of the diagram on the liquid where the liquid protrudes the most is $\mathrm{D}$. The vertical depth of this point from the horizontal free surface of the water layer is $\mathrm{d}$. $\mathrm{\rho }$ is density of water and $\mathrm{g}$ is acceleration due to gravity. Mark the CORRECT relation(s)

Which instrument is used to measure atmospheric pressure ?

Define atmospheric pressure.

Mention different units of atmospheric pressure?

What is absolute pressure in Pascal?

With the increasing altitude, gauge pressure: