Question

Refractive index of the medium is \( \mu \) and wavelength is \( \lambda \), then which of the following proportionality relation is correct?

• A. \( \mu \propto \frac{1}{\lambda^2} \)
• B. \( \mu \propto \lambda^2 \)
• C. \( \mu \propto \frac{1}{\lambda} \)
• D. \( \mu \propto \lambda \)

Hint:

In most transparent materials, the refractive index decreases as the wavelength of light increases.

Answer 1

The Correct Option is C

Step 1: Understanding refractive index.
The refractive index \( \mu \) of a medium is related to the speed of light in the medium. The refractive index decreases with the increase in wavelength.
Step 2: Correct proportionality relation.
For most materials, the refractive index is inversely proportional to the wavelength: \[ \mu \propto \frac{1}{\lambda} \]
Step 3: Conclusion.
The correct relation is \( \mu \propto \frac{1}{\lambda} \), so the correct answer is (C).