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Question
Which of the following methods can be used to measure the speed of light in water?
Options
Roemer method
Fizeau method
Foucault method
Michelson method
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Solution
Foucault method
Foucault method can be used to measure the speed of light in water. One of the advantage of this method is that one can put some transparent medium (or water) between two mirrors to measure the speed of light in that medium (or water). Foucault observed that the velocity of light in water is less than that in the air.
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