Question

The percentage absolute humidity of air becomes equal to the percentage relative humidity, when:

• A. absolute humidity of air is equal to relative humidity
• B. saturated humidity of air is equal to relative humidity
• C. air is almost or completely dry
• D. air is almost or completely saturated

Hint:

Remember: Relative humidity compares absolute humidity with its maximum possible value. When both are equal, the air is saturated and percentages match.

Answer 1

The Correct Option is D

Step 1: Define absolute humidity. Absolute humidity is the actual mass of water vapor per unit volume of air.

Step 2: Define relative humidity. Relative humidity (RH) is the ratio of actual water vapor content to the maximum possible (saturation) content at that temperature, expressed as a percentage. \[ RH = \frac{AH}{SH} \times 100 \] where \(AH =\) absolute humidity, \(SH =\) saturated humidity.

Step 3: Condition for equality. For percentage absolute humidity = percentage relative humidity, we must have: \[ \frac{AH}{SH} \times 100 = AH \, (%) \] This occurs when \(AH = SH\), i.e., when the air is completely saturated. \[ \boxed{\text{Air is almost or completely saturated}} \]