Question

why is barometric height is used as a unit to express the atmospheric pressure?

Answer 1

. The working of barometer is based on balancing the weight of mercury in the glass tube against the atmospheric pressure. If the weight of mercury is less than the atmospheric pressure, the mercury level in the glass tube rises. If the weight of mercury is more than the atmospheric pressure, the mercury level falls.Atmospheric pressure is basically the weight of air in the atmosphere above the reservoir, so the level of mercury continues to change until the weight of mercury in the glass tube is exactly equal to the weight of air above the reservoir. This is the reason why height of mercury column is the measure of atmospheric pressure.

Answer 2

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