Ultrasound has frequency of vibration

Options

A. between 20 and 20,000 Hz
B. below 20 Hz
C. above 20,000 Hz
D. between 500 and 10,000 Hz

Explanation

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

### Step-by-Step Solution:

1. **Understanding Ultrasound**:
- Ultrasound refers to sound waves that have frequencies higher than the upper limit of human hearing.

2. **Frequency Range of Human Hearing**:
- The normal range of human hearing is between 20 Hz and 20,000 Hz (20 kHz). Sounds below 20 Hz are called infrasound, while sounds above 20 kHz are classified as ultrasound.

3. **Identifying the Frequency of Ultrasound**:
- Since ultrasound is defined as sound with frequencies above 20 kHz, we can conclude that ultrasound has a frequency greater than 20,000 Hz.

4. **Conclusion**:
- Therefore, the frequency of vibration of ultrasound is **greater than 20,000 Hz**.

### Final Answer:
Ultrasound has a frequency of vibration **greater than 20,000 Hz**.

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