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Explain with reason : When monochromatic light is incident on a surface separating two media , then both reflected and refracted light have the same frequency as the incident frequency .
Answers
Why would the frequency change? monochromatic light is a light of 1 colour which implies it only has 1 frequency. It will not defract like white light to show lights of different frequencies as monochromatic light has only one frequency.Thus incident frequency is equal the refracted and reflected frequency as it is all the same frequency. [ P.S i didnt know what monochromatic light meant so i did look that up in the internet but the rest of the answer is what i think it should be. please check other answers to be sure]
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When monochromatic light travels from one medium to another , it's speed changes, so it's wavelength changes but frequency remain same. Reflection and refraction arise due to interaction of incident light with atomic constitution of matter which vibrate with same frequency as that of incident light .