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The wavelengths for the light of red and blue colours are roughly 7 X 10-7 m and 4 X 10-7 m respectively. Which colour has the greater speed in vacuum? Which colour has the greater speed in glass?
In vacuum both the colours have the same speed.
In glass, red colour has a greater speed.
Concept: Refraction of Light - Refraction of Light Through a Glass Block and a Triangular Prism
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