CBSE-XI-Physics
21: Speed of Light
- #3Which of the following methods can be used to measure the speed of light in water?
(a) Roemer method
(b) Fizeau method
(c) Foucault method
(d) Michelson methoddigAnsr: bAns : (b) the image will be shifted a little later than the object
Light rays emitting from a source have to cover some optical distance to form an image of the source on the other side of the lens. So, when a light source is shifted by some distance on the principal axis, then the light rays emitting from the new position of the source take some time to form a shifted image of the object on the other side of the lens. However, this delay is very small because the speed of light has a very larger value.
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