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प्रश्न
The speeds of red light and yellow light are exactly same
विकल्प
in vacuum but not in air
in air but not in vacuum
in vacuum as well as in air
neither in vacuum nor in air
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उत्तर
in vacuum but not in air
Different wavelengths travel at different speeds through different media. In vacuum, the speeds of both the red light and yellow light are same but are different in air due to some optical density of air. Both wavelengths act in a different way in the air.
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