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Question
What is the speed of light in a medium of refractive index `6/5` if its speed in air is 3,00,000 km/s?
Solution
Given:
Speed of light in air = 3,00,000 km/s
Refractive index of the medium = 6/5
Speed of light in the given medium = ?
Applying formula for refractive index, we get:
Refractive index of a medium = (Speed of light in air) / (Speed of light in medium)
or
(Speed of light in medium) = (Speed of light in air) / (Refractive index of a medium)
= 3,00,000 / (6/5)
= 2,50,000 km/s
RELATED QUESTIONS
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| Material medium | Refractive index | Material medium | Refractive index |
| Air | 1.0003 | Canada Balsam | 1.53 |
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| Water | 1.33 | Rock salt | 1.54 |
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| Fused quartz | 1.46 | Dense flint glass | 1.65 |
| Turpentine oil | 1.47 | Ruby | 1.71 |
| Benzene | 1.50 | Sapphire | 1.77 |
| Crown glass | 1.52 | Diamond | .42 |
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