Question about the index of refraction, n=c/v?

If the speed of light in air is 1.00c and the speed of light in glass is 0.67c, how is this consistent with n=c/v.

I don't really understand this, please help

2 Answers

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  • 6 years ago
    Best Answer

    refractive index = n = c/v = c/0.67c = 1.49

    This means the refractive index of glass is 1.49, meaning that light travels 1.49 times slower in glass than it does in vacuum ( i.e.speed of light in glass = c/1.49 = 0.67c)

    PS

    speed of light in a vacuum = c.

    n for a vacuum = c/c = 1

    n for air at STP = 1.000277

  • 6 years ago

    This is very simple.

    An optically denser medium has a higher refractive index. This is because it refracts the light ray more and it bends towards the normal.

    An optically rarer medium has a lower refractive index. This is because it refracts the light ray less and it bends away from the normal.

    From this you can understand that glass is optically denser than air.

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