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Question
What is ultrasound ? What is the difference between ordinary sound and ultrasound ?
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Solution
Ultrasound waves are high-frequency sound waves. Due to higher frequency, they can penetrate into matter to a large extent.
We can differentiate between ordinary and ultrasonic waves as :
| Audible sound waves | Ultrasound waves |
| They have a frequency range of 20 Hz–20,000 Hz | They have frequencies above 20,000 Hz |
| These sounds are audible to human ears. | These sounds are inaudible to human ears. |
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