What is the frequency range of ultrasound ?

Options

A. Less than. 10 Hz
B. Less than 20 Hz
C. Greater than 20,000 hz
D. Between 20 to 20,000 hz

Answer

To determine the frequency range of ultrasound, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Sound Frequencies**:
- Sound is classified based on its frequency, measured in Hertz (Hz).
- The human ear can typically hear sounds in the frequency range of about 20 Hz to 20,000 Hz (20 kHz).

2. **Defining Ultrasound**:
- Ultrasound refers to sound waves that have frequencies higher than the upper limit of human hearing.
- Therefore, ultrasound is defined as sound waves with frequencies greater than 20,000 Hz (20 kHz).

3. **Identifying the Frequency Range**:
- Since ultrasound is above 20 kHz, any sound with a frequency greater than 20,000 Hz falls into this category.
- Frequencies below 20 Hz are classified as infrasonic, which is not relevant to ultrasound.

4. **Conclusion**:
- The frequency range of ultrasound is greater than 20,000 Hz.

### Final Answer:
The frequency range of ultrasound is greater than 20,000 Hz.

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