Answer to Question #112420 in Physics for Sarah

Question

A manometer is used to measure the pressure of a gas supply, as shown in the diagram. The left hand end of the manometer is left open to the atmosphere.
If the liquid used is water (density = 1000 kg/m3) and the value of h is 5 cm, what is the pressure of the gas?
A. 500 Pa above atmospheric pressure.

B. 500 Pa below atmospheric pressure.
C. The same as atmospheric pressure.
D. 50 000 Pa above atmospheric pressure.

Answer 1

$$P-P_a=\rho gh=(1000)(10)(0.05)=500\ Pa$$

Answer: A. 500 Pa above atmospheric pressure.