CBSE-XI-Physics

21: Speed of Light

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  • #2
    Which of the following methods can be used to measure the speed of light in laboratory?
    (a) Roemer method
    (b) Fizeau method
    (c) Foucault method
    (d) Michelson method
    digAnsr:   a
    Ans :
    (a) 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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