The instrument used to meausre wind velocity is

Options

A. Hydrometer
B. Anemometer
C. Photometer
D. Potometer

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the instrument used to measure wind velocity.

2. **Analyzing the Options:**
- **Option 1: Hydrometer**
- A hydrometer is used to measure the specific gravity of liquids. The prefix "hydro" refers to water or liquids, not air.
- **Option 2: Anemometer**
- An anemometer is specifically designed to measure wind velocity. The prefix "anemo" relates to wind or air.
- **Option 3: Photometer**
- A photometer measures light intensity. The prefix "photo" refers to light, not wind.
- **Option 4: Photometer (repeated)**
- This is the same as option 3 and measures light intensity.

3. **Identifying the Correct Instrument:**
- From the analysis, the only instrument that measures wind velocity is the anemometer.

4. **Conclusion:**
- Therefore, the correct answer to the question is **Option 2: Anemometer**.

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