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प्रश्न
A ray of light of wavelength 600 nm propagates from air into a medium. If its wavelength in the medium becomes 400 nm, the refractive index of the medium is ______.
विकल्प
1.4
1.5
1.6
1.8
उत्तर
A ray of light of wavelength 600 nm propagates from air into a medium. If its wavelength in the medium becomes 400 nm, the refractive index of the medium is 1.5.
Explanation:
We know that refractive index and wavelength have an inverse relation. Therefore, the refractive index is stated to be inversely proportional to the wavelength.
`n = c/(flambda)`
Given: `lambda_1 = 600 "nm", lambda_2 = 400 "nm"`
To find: Refractive index (n)
`n_1lambda_1 = n_2lambda_2`
`n_2/n_1 = lambda_1/lambda_2`
`n_2 = 600/400` [∵ n1 = 1]
`n_2 = 1.5`
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