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 glass of refractive index 1.55?

Answer 1

Let λ₁ and λ₂ be the wavelengths of light in water for 400 nm and 700 nm (wavelengths in vacuum) respectively.

Let λ_v be the wavelength of light in vacuum.

λ₁ = λ_v/n = \(\frac{400×10^{-9}}{1.55}\) = 258.06 x 10⁻⁹ m

λ₂ = λ_v/n = \(\frac{700×10^{-9}}{1.55}\) = 451.61 x 10⁻⁹ m

The wavelength range seen when white light is passed through the glass would be 258.06 nm to 451.61 nm.