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प्रश्न
A ray of light travels a distance of 12.0 m in a transparent sheet in 60 ns. The refractive index of the sheet is ______.
पर्याय
1.33
1.50
1.65
1.75
उत्तर
A ray of light travels a distance of 12.0 m in a transparent sheet in 60 ns. The refractive index of the sheet is 1.50.
Explanation:
The refractive index can be calculated as,
`mu = c/v`
Where µ is the refractive index, c is the speed of light in air, `v` is the speed of light in the second medium.
Given: Distance d = 12 m, time t = 60 ns = 60 × 10-9 sec
`v = "distance"/"time"`
`v = (12/60) xx 10^9`
`v = (1/5) xx 10^9` m/s
`mu = (3 xx 10^8)/((1"/"5) xx 10^9)`
`mu = 3 xx 10^8 xx 5 xx 10^-9`
μ = 1.5
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