^Infra red waves

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^Infra red waves

(a) Also called heat waves & are produced by hot bodies and molecules.

(b) Properties: Heating effect, reflection, refraction, diffraction & propagation through fog.

(c) Used

1. In taking photographs during the conditions of fog, smoke etc. as these waves are scattered less than visible rays and hence can travel longer distances through atmosphere under fog, smoke etc.
2. In weather forecasting
3. In checking the purity of chemicals
4. In the study of molecular structures
5. For producing dehydrated fruits
6. In green houses to keep the plants warm
7. To provide electrical energy to satellites using solar cells.
8. To treat muscular strain.
9. In solar water heaters and cookers.