The diagram below shows a simple mercury barometer. The mercury level is at a height $h$ when the atmospheric pressure is $10^{5}$ Pa.

What is the pressure at P?

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Solution

In a barometer, atmospheric pressure is directly proportional to the height of the mercury level.
Now, height $h$ corresponds to the pressure of 1,00,000 Pa.
So height 0.4 h will correspond to the pressure of 0.4 $\times$ 1,00,000 = 40,000 Pa.
Hence, pressure at P is 40,000 Pa.

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Q. The diagram below shows a simple mercury barometer. The mercury level is at a height

h

when the atmospheric pressure is

10^{5}

Pa.

What is the pressure at P?

Q. The height of mercury barometer is

h

when the atmospheric pressure is

10^{5} P a

,The pressure at

x

in the shown diagram is

Q. Explain how is the height of mercury column in tube of a simple barometer is a measure of the atmospheric pressure.

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The diagram below shows a simple mercury barometer. The mercury level is at a height h when the atmospheric pressure is 105 Pa. What is the pressure at P?

In a barometer, atmospheric pressure is directly proportional to the height of the mercury level. Now, height h corresponds to the pressure of 1,00,000 Pa. So height 0.4 h will correspond to the pressure of 0.4 × 1,00,000 = 40,000 Pa. Hence, pressure at P is 40,000 Pa.

The diagram below shows a simple mercury barometer. The mercury level is at a height $h$ when the atmospheric pressure is $10^{5}$ Pa.

What is the pressure at P?

In a barometer, atmospheric pressure is directly proportional to the height of the mercury level.
Now, height $h$ corresponds to the pressure of 1,00,000 Pa.
So height 0.4 h will correspond to the pressure of 0.4 $\times$ 1,00,000 = 40,000 Pa.
Hence, pressure at P is 40,000 Pa.