Question

Determine the change in wavelength of light during its passage from air to glass, if the refractive index of glass with respect to air is 1.5 and the frequency of light is 5 x 10¹⁴ Hz. Find the wave number of light in glass (velocity of light in air c = 3 x 10⁸ m/s).

Answer 1

Given: _aμ_g = 1.5, v = 5 x 10¹⁴ Hz.

To find : 

a. Change in wavelength (Δλ) 

b. Wave number of light in glass (\(\overline{v}_s\))

Formulae:

Calculation: Using formula (c),

Ans: a. Change in wavelength is 2000 Å 

b. Wave number of light in glass is 2.5 x 10⁶ m^–1