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Question
Solve the following example.
Speed in first medium, v1 = 3 × 108 m/s
Speed in second medium, v2 = 2 × 108 m/s
Then 2n1 = ?
Solution
Given: Speed of light in first medium (v1) = 3 × 108 m/s,
Speed of light in second medium (v2) = 2 × 108 m/s
To find: Refractive index of the second medium with respect to the first medium (2n1)
Formula: 2n1 = `"v"_1/"v"_2`
Calculation: From formula,
2n1 = `(3 xx 10^8)/(2 xx 10^8)` = 1.5
Refractive index of the second medium with respect to the first medium (2n1) is 1.5.
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