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If in a medium, the speed of light is 1.5 × 108 m/s how much will the absolute refractive index of that medium be?
Solve the example.
If the speed of light in a medium is 1.5 × 108 m/s, what is the absolute refractive index of the medium?
Solution 1
Absolute refractive index of a medium μ = `"Speed of light in vaccum"/ "Speed of light in the medium"`
⇒ μ = `(3 xx 10^8)/(1.5 xx 10^8) = 2`
Solution 2
Given: Speed of light in medium (v2) = 1.5 × 108 m/s,
velocity of light in vacuum (v1) = 3 × 108 m/s
To find: Absolute refractive index (n)
Formula: n = `"v"_1/"v"_2`
Calculation: From the formula,
n = `(3 xx 10^8)/(1.5 xx 10^8)` = 2
The absolute refractive index of the medium is 2.
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