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What are ultrasonic waves ?...

What are ultrasonic waves ?

A

Sound waves having frequency shorter than audio frequency range

B

Sound waves produced in a vacuum

C

Sound waves having frequency higher than audio-frequency range

D

None of these

Text Solution

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The correct Answer is:
**Step-by-Step Solution:** 1. **Definition of Ultrasonic Waves**: Ultrasonic waves are sound waves that have frequencies higher than the audible range for humans. Specifically, they are sound waves with frequencies greater than 20 kHz (20,000 Hz). 2. **Categories of Sound Waves**: Sound waves can be categorized into three main types based on their frequency: - **Infrasonic Waves**: These are sound waves with frequencies less than 20 Hz. Humans cannot hear these low frequencies. - **Audible Waves**: These are sound waves with frequencies ranging from 20 Hz to 20 kHz. This is the range that humans can hear. - **Ultrasonic Waves**: These are sound waves with frequencies greater than 20 kHz. Humans cannot hear these high frequencies. 3. **Characteristics of Ultrasonic Waves**: - Ultrasonic waves cannot be heard by the human ear. - They are used in various applications, such as medical imaging (ultrasound), cleaning delicate items, and in certain types of pest control. 4. **Conclusion**: Therefore, ultrasonic waves are defined as sound waves that have frequencies higher than 20 kHz, which are beyond the audible range for humans.
**Step-by-Step Solution:** 1. **Definition of Ultrasonic Waves**: Ultrasonic waves are sound waves that have frequencies higher than the audible range for humans. Specifically, they are sound waves with frequencies greater than 20 kHz (20,000 Hz). 2. **Categories of Sound Waves**: Sound waves can be categorized into three main types based on their frequency: - **Infrasonic Waves**: These are sound waves with frequencies less than 20 Hz. Humans cannot hear these low frequencies. - **Audible Waves**: These are sound waves with frequencies ranging from 20 Hz to 20 kHz. This is the range that humans can hear. - **Ultrasonic Waves**: These are sound waves with frequencies greater than 20 kHz. Humans cannot hear these high frequencies. ...
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