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CBSE Class 9 Answered

REFRACTIVE INDEX
Asked by ravikiran | 09 Aug, 2009, 12:06: PM
answered-by-expert Expert Answer

When light travels from one medium (air) into another (glass, water), it's speed is reduced.

Refractive index of the second medium (glass, water) with respect to first (air) 

                                           = Light Speed in first medium (air) / Light speed in second medium (glass, water).

Mirage is due to the variation of refractive index of air (hot, cold) from ground up i.e. with respect to height from ground.

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TopperLearning..

Answered by | 09 Aug, 2009, 01:45: PM

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