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Question
The speed of light in air is 3 × 108 m/s. In medium X its speed is 2 × 108 m/s and in medium Y the speed of light is 2.5 × 108 m/s Calculate:
(a) air nx
(b) air nY
(c) x nY
Solution
(a) air nx = (Speed of light in air) / (Speed of light in medium X)
= (3 × 108) / (2 × 108)
= 1.5
(b) air n Y = (Speed of light in air) / (Speed of light in medium Y)
= (3 × 108) / (2.5 × 108)
= 1.2
(c) x nY = (Speed of light in medium X) / (Speed of light in medium Y)
= (2 × 108) / (2.5 × 108)
= 0.8
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