Physics
Grade-8
Easy
Question
Metal cracks are detected using ________ sounds.
- Infra
- Ultra
- Audible
- None
Hint:
High frequency
The correct answer is: Ultra
- Metal cracks are detected using high frequency or ultrasound.
- Sounds above 20kHz of frequency are known as ultrasounds.
- So, the correct option is b.
- Ultrasound or high frequency sound waves is transmitted into materials to characterize the material or for crack detection.
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