Question

At an absolute pressure of 101.3 kPa and a temperature of 15°C, what is the head of air (R= 287 J/kgK) equivalent to a pressure of 75 mm of water?

a. 60.98 m
b. 65.33 m
c. 58.28 m
d. 62.58 m

Answer 1

To determine the head of air equivalent to a pressure of 75 mm of water, we can use the formula for the height of a column of fluid. The height is calculated to be approximately 60.98 meters.

Step-by-step explanation:

To determine the head of air equivalent to a pressure of 75 mm of water, we need to calculate the height of a column of air with the same pressure. The formula to calculate the height of a column of fluid is:

where pressure is the given pressure, density is the density of air, and g is the acceleration due to gravity. Using the given values:

pressure = 75 mm H2O = 9.81 × 75 Pa = 735.75 Pa

density of air = 1.20 kg/m³

g = 9.81 m/s²

Substituting the values into the formula:

height = (735.75 / 1.20) / 9.81 ≈ 60.98 meters

Therefore, the head of air equivalent to a pressure of 75 mm of water is approximately 60.98 meters.