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Question
White light consists of wavelengths from 400 nm to 700 nm. What will be the wavelength range seen when white light is passed through a glass of refractive index 1.55?
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Solution
`lamda_(glass) = lamda_(air)/µ`
Where:
λair = wavelength in air
μ = refractive index of the medium (here, glass = 1.55)
Minimum wavelength in glass = `400/1.55 = 258.06` nm
Maximum wavelength in glass = `700/1.55 = 451.61` nm
Wavelength range in glass: 258 nm to 452 nm
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