The wavelength of light coming from a sodium source is 589 nm. Its wavelength in crown glass having refractive index 1.52 is
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 387.5 nm
Wavelength in a medium: $\lambda_\text{medium} = \frac{\lambda_\text{vacuum}}{\mu}$
Given: $\lambda_\text{vacuum} = 589\ \text{nm}$, $\mu = 1.52$
Wavelength in crown glass:
$\lambda_\text{glass} = \frac{589}{1.52} \approx 387.5\ \text{nm}$
Final Answer: $\lambda_\text{glass} \approx 388\ \text{nm}$