SI unit of pitch is :

Options

A. Hertz
B. metre
C. m/sec
D. second

Explanation

To find the SI unit of pitch, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Pitch**:
- Pitch is a perceptual property of sounds that allows us to classify them as high or low. It is closely related to the frequency of sound waves.

2. **Define Frequency**:
- Frequency refers to the number of vibrations or cycles per second of a sound wave. It is measured in Hertz (Hz).

3. **Relate Pitch to Frequency**:
- Since pitch is essentially a perception of the frequency of sound, it is measured in the same unit as frequency.

4. **Identify the SI Unit**:
- The SI unit of frequency is Hertz (Hz). Therefore, the SI unit of pitch is also Hertz (Hz).

5. **Conclusion**:
- The SI unit of pitch is Hertz (Hz).

### Final Answer:
The SI unit of pitch is Hertz (Hz).

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