NCERT Example 10.1 - Wave Optics
Question: (a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency. Explain why. (b) When light travels from a rarer to a denser medium, the speed decreases. Does this decrease in speed imply a reduction in energy?
Answer: (a) Frequency is set by the source / boundary oscillation — **unchanged**. (b) **No** energy reduction of photons; speed drop is due to medium interaction, E = hν same.
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