Question

The colour of light, which is deviated the least by a prism in the spectrum of white light, is

• A. red
• B. green
• C. violet
• D. yellow

Answer 1

The correct option is A

red

Explanation

1. The ray of light bends while travelling from one medium to another due to the phenomena of refraction.
2. As we know $v=\mathit{\nu }\lambda$ where $v$ is the velocity of light, $\mathit{v}$is the frequency of light and $\lambda$ is the wavelength of light.
3. The frequency of light remains constant in both the media.⇒$v\propto \lambda$
4. So, the variations in wavelength and velocity are proportional.
5. If the wavelength of the light is large then its velocity will also be large.
6. The wavelength of the light is inversely proportional to the amount of scattering.
7. As we know, red has the longest wavelength; so, it bends the least.

Hence the correct option is (A).