The most comfortable value for RH is about

Options

A. `10%`
B. `30%`
C. `50%`
D. `90%`

Answer

To solve the question regarding the most comfortable value for Relative Humidity (RH), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Relative Humidity (RH)**:
- Relative Humidity is defined as the ratio of the current absolute humidity to the highest possible absolute humidity at a given temperature. It is expressed as a percentage.

2. **Interpret the Options**:
- The options provided are 10%, 30%, 50%, and 90%. We need to determine which of these values is considered the most comfortable for humans.

3. **Analyze the Meaning of 100% RH**:
- A reading of 100% RH indicates that the air is fully saturated with water vapor. At this level, the air cannot hold any more moisture, which can lead to conditions such as rain.

4. **Determine Comfort Levels**:
- Generally, relative humidity levels that are too low (like 10% or 30%) can cause dryness, while levels that are too high (like 90%) can make the air feel heavy and uncomfortable.

5. **Identify the Most Comfortable Level**:
- Based on common understanding and studies, a relative humidity level of around 50% is often cited as the most comfortable for human beings. This level provides a balance where the air is neither too dry nor too humid.

6. **Conclusion**:
- Therefore, the most comfortable value for Relative Humidity (RH) is **50%**.

### Final Answer:
The most comfortable value for RH is **50%**.

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