Question

The wavelength of sodium light in glass if it is 589.3 nm in air is (The refractive index of glass is 1.5).

• A. 589.3 x 1.5 nm
• B. (589.3/1.5) nm
• C. 589.3 nm
• D. None of the above

Answer 1

Answer: (B)

(589.3/1.5) nm

Answer 2

$n=\frac{c}{v}=\frac{f\,\lambda_a}{f\,\lambda_g}.Hence\,\lambda_g=\lambda_a/n$