Question

A light ray of frequency $\nu$ and wavelength $\lambda$ enter a liquid of refractive index $3/2$. The ray travels in the liquid with:

• A. frequency $\nu$ and wavelength $\left(\frac{2}{3}\right)\lambda$
• B. frequency $\nu$ and wavelength $\left(\frac{3}{2}\right)\lambda$
• C. frequency $\nu$ and wavelength $\lambda$
• D. frequency $\left(\frac{3}{2}\right)$ and wavelength $\nu$

Answer 1

The correct option is A frequency $\nu$ and wavelength $\left(\frac{2}{3}\right)\lambda$

Frequency never changes from medium to medium and the wavelength in a medium is $\frac{{\lambda }^{\prime }\times {\mu }^{\prime }}{\mu }$ where ${\lambda }^{\prime }$ and ${\mu }^{\prime }$ is wavelength and refractive index in air and $\mu$ is refractive index of liquid.

$\therefore wavelength=\frac{2}{3}\lambda$