Question

A manomter is connected to a gas containing bulb. The open arm reads 43.7 cm whereas the arm connected to the bulb reads 15.6 cm. If the baremetric pressure is 743 mm mercury, what is the pressure of gas in bar ?

Answer 1

Difference of mercury levels in the two arms `=43.7-15.6 cm=28.1" cm"`
As level in the limb connected to the gas bulb is lower than that of open limb, this means pressure of gas is more than the atmospheric pressure.
`:. `Pressure of the gas in the bulb =Barometric pressure+Difference of mercury levels
=74.3 cm +28.1 cm=102.4 cm
`=(102.4)/(76)atm=(102.4)/(76)xx1.01325" bar"=1.365 " bar "`