A ray of light of wavelength 5400 Å suffers refraction from air to glass. Taking _aμ_g = 3/2, find the wavelength of light in glass.

As we know that,

$_{\text{a}}\text{μ}_{\text{g}} = \dfrac{\text {wavelength of light in air}}{\text {wavelength of light in glass}} \\[0.5em]$

Given,

Refractive index of glass with respect to air is given by _aμ_g = $\dfrac{3}{2}$

Wavelength of light in air = 5400 Å

Substituting the values in the formula above we get,

$\dfrac{3}{2} = \dfrac{\text {wavelength of light in air}}{\text{wavelength of light in glass}} \\[0.5em] \dfrac{3}{2} = \dfrac{5400}{\text {wavelength of light in glass}} \\[0.5em] \text {wavelength of light in glass} = \dfrac{5400}{\dfrac{3}{2}} \\[0.5em] \text {wavelength of light in glass} = 5400 \times \dfrac{2}{3} \\[0.5em] \text {wavelength of light in glass} = 3600 \\[0.5em]$

Hence, wavelength of light in glass = 3600 Å