Question

A Closed U-tube manometer has a gas at one end and vacuum at other end, if the height difference of the liquid (density = 10 kg/m^3) in the manometer in 5 cm, what is the pressure of the gas?

(a) 10 N/m^2

(b) 5 N/m^2

(c) 2.5 N/m^2

(d) 1 N/m^2

The question was asked by my college professor while I was bunking the class.

My query is from Measurement of Pressure in chapter Temperature and Pressure of Basic Chemical Engineering

Answer 1

The correct choice is (b) 5 N/m^2

Explanation: Pressure of the gas = dgh = 10*10*0.05 = 5 N/m^2.