The units of RH are

Options

A. `kg-m^(-3)`
B. kg
C. `kg-m^2`
D. none of these

Answer

To determine the units of Relative Humidity (RH), we can follow these steps:

### Step 1: Understand the Definition of Relative Humidity
Relative Humidity (RH) is defined as the ratio of the actual water vapor content in the air to the maximum (saturated) water vapor content that the air can hold at the same temperature.

### Step 2: Express the Ratio
Mathematically, RH can be expressed as:
\[ RH = \frac{\text{Actual Water Vapor Content}}{\text{Saturated Water Vapor Content}} \]

### Step 3: Analyze the Ratio
Since RH is a ratio of two quantities that are both measured in the same units (for example, grams of water vapor per cubic meter of air), the units cancel out.

### Step 4: Conclusion on Units
Because RH is a ratio, it is often expressed as a percentage. However, as a ratio itself, it has no units. Therefore, the units of RH are:
- No unit (dimensionless).

### Final Answer
The units of Relative Humidity (RH) are: **No unit**.

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