A water-filled manometer is used to measure the pressure in an air-filled tank. One leg of the manometer is open to atmosphere. For a measured manometer deflection of 250 cm water, determine the absolute pressure and the gauge pressure of the tank. Barometric pressure is 101.3 kPa abs.

P (abs) = 103.8 KPa

P (gauge) = 2.5 KPa

Explanation:

Given that

Manometer deflection (h) = 250 cm water

Barometric pressure = 101.3 kPa abs

As we know that Barometric measure atmospheric pressure while manometer reads gauge pressure or local pressure.

We also know that density (ρ) of water is 1000 kg/m³.

Gauge pressure P (gauge) = ρ g h

P (gauge) = 1000 x 10 x 0.25 = 2.5 KPa (take g = 10 m/s²)

P (gauge) = 2.5 KPa

P (atm) = 101.3 KPa

Absolute pressure = atmospheric pressure + gauge pressure

P (abs) = P (atm) + P (gauge)

P (abs) = 101.3 + 2.5 KPa

P (abs) = 103.8 KPa