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Question
In the original Fizeau method, the light travelled 8.6 km and then returned. What could be the difficulty if this distance is taken as 8.6 m?
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Solution
There is no difficulty if the distance travelled by light is decreased. In this method, light has to travel a large distance of 8.6 km. So, the intensity of the light decreases considerably and the final image becomes dim. If somehow this distance is decreased, the final image is dark due to the increased light intensity.
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