question_answer

In a mercury barometer, at sea level, the normal pressure of the air (one atmosphere) acting on the mercury in the dish supports a 76 cm column of mercury in a closed tube. If you go up in the air, until the density has fallen to half its sea level value, what height of mercury column would you expect?

Answer:

                Pressure exerted by a gas is directly proportional to its density. When we go high up in air at a point where the density of air falls to half its sea level value, the pressure also reduces to half its sea-level value. Hence the height of mercury column is also halved i.e., it becomes 38 cm.