Question
- How are infrared waves produced? Write their one important use.
- The thin Ozone layer on top of the stratosphere is crucial for human survival. Why?
✓
Answer
- Infrared waves are produced by hot bodies and molecules. Important use.
- 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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