Question

According to Huygens principle, during refraction of light from air to a denser medium

• A. Wavelength and speed increase
• B. Wavelength decreases but speed increases
• C. Wavelength and speed decrease
• D. Wavelength increases but speed decreases

Answer 1

The correct option is C Wavelength and speed decrease

During the refraction of light from air to denser medium, speed and wavelength of the light decreases but its frequency remains the same.

Speed of light in denser medium $v=\frac{c}{n}$

where $c$ is the speed of light in air.

Also wavelength of light in denser medium ${\lambda }_m=\frac{\lambda }{n}$

where $\lambda$ is the wavelength of light in air.