Question

The Refractive index of a medium is

• A. directly proportional to the wavelength of light in air
• B. inversely proportional to the wavelength of light in air
• C. inversely proportional to the square of the wavelength of light in air
• D. directly proportional to the square of the wavelength of light in air

Answer 1

The correct option is B

inversely proportional to the wavelength of light in air

Explanation

1. If the refractive index of a medium is high then the velocity of light decreases in that medium.
2. $\mu =\frac{c}{v}$ where is the refractive index, c is the velocity of light in air or vacuum and v is the velocity of light in the medium.
3. Now, $v=f\lambda$. So, we get, $\mu =\frac{c}{f\lambda }$.

Hence, option (B) is the correct answer.