Question

In a depillaring face of an underground coal mine, both wet and dry bulb temperatures are 30 ℃. The relative humidity of the face environment, in percentage, is

• A. 0
• B. 30
• C. 60
• D. 100

Hint:

When the wet and dry bulb temperatures are equal, the relative humidity is 100%, indicating complete saturation of air.

Answer 1

The Correct Option is D

Step 1: Understand the concept of relative humidity.
Relative humidity (\(RH\)) is given by the formula: \[ RH = \frac{T_{{wet}} - T_{{dry}}}{T_{{wet}}} \times 100 \] Where:
\(T_{{wet}}\) is the wet bulb temperature.
\(T_{{dry}}\) is the dry bulb temperature.
Step 2: Apply the given values.
Since both the wet and dry bulb temperatures are equal (30 ℃), it means there is no evaporation, indicating that the relative humidity is 100%.