What is the Specific Volume when the Dry Bulb Temperature is 120°F and the Relative Humidity is 25%?

To determine the specific volume of moist air at a given dry bulb temperature and relative humidity, it is important to use psychrometric principles. The specific volume of air is influenced by both the temperature and the humidity level of the air.

At a dry bulb temperature of 120°F and a relative humidity of 25%, the specific volume can be calculated using psychrometric charts or formulas. The process involves finding the saturation pressure at the specified temperature, then calculating the actual vapor pressure based on the relative humidity, followed by computing the specific volume using these values.

For this scenario, the specific volume typically increases with higher dry bulb temperatures and decreases with lower relative humidity. Given the specific conditions of 120°F and 25% relative humidity, the calculated specific volume aligns with the value identified as 15 ft³/lb.

Other values provided do not reflect the correct relationship between temperature, humidity, and specific volume, as they either underestimate or overestimate the expected specific volume for these conditions.