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Sound — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceSound3 Marks
Question
Explain how, flaws (or defects) in a metal block can be detected by using ultrasound.
✓

Answer

Ultrasound waves are made to pass through one face of the metal block and ultrasound detectors are placed on the opposite face of the block to detect the transmitted ultrasound waves.
  1. If the ultrasound waves pass uninterrupted through all parts of the metal block, then the block is flawless.
  2. However, if the ultrasound waves are not able to pass through a part of the metal block and get reflected back, then there is a flaw in the metal block.

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