Question

Light waves entering a medium with higher refractive index undergo

• A. Change in velocity and frequency but not wavelength
• B. Change in wavelength and frequency but not velocity
• C. Change in velocity and wavelength but not frequency
• D. Change in velocity, frequency and wavelength

Hint:

Frequency is "stubborn"—it never changes when moving between media. Velocity and Wavelength always change together.

Answer 1

The Correct Option is C

Step 1: Concept
When light travels from one medium to another, its properties change based on the refractive index ($n$).

Step 2: Analysis of Frequency
Frequency is a property of the source and remains constant regardless of the medium the wave enters.

Step 3: Analysis of Velocity and Wavelength
The velocity decreases ($v = c/n$) in a denser medium. Since $v = f\lambda$ and $f$ is constant, the wavelength ($\lambda$) must also decrease.

Step 4: Conclusion
Both velocity and wavelength change, but frequency remains unchanged. Final Answer: (C)