CBSE-XI-Physics
21: Speed of Light
- #2The speeds of red light and yellow light are exactly same
(a) in vacuum but not in air
(b) in air but not in vacuum
(c) in vacuum as well as in air
(d) neither in vacuum nor in airdigAnsr: aAns :
(c) Foucault method
Foucault gave the first laboratory method to find the velocity of light. He obtained a value of `` 2.98\times {10}^{8}\,\mathrm{\,m\,}/\,\mathrm{\,s\,}`` from his measurements.
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