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Alternating Current — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsAlternating Current2 Marks
Question
  1. How are infrared waves produced? Write their one important use.
  2. The thin Ozone layer on top of the stratosphere is crucial for human survival. Why?
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Answer

  1. Infrared waves are produced by hot bodies and molecules. Important use.
  2. To treat muscular strains/To reveal the secret writings on the ancient walls/For producing dehydrated fruits/Solar Heater/Solar cooker Ozone layer protects us from harmful U-V rays.

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