Question

The angle of minimum deviation of a ray of light of glass prism is greatest for the light of colour:
A. Violet
B. Orange
C. Yellow
D. Red

Answer 1

Hint:White light passing through a glass prism creates a spectrum of white. White light dispersion is the term for this phenomenon. White light is made up of a variety of colours or wavelengths of light i.e., the VIBGYOR pattern.

Complete step by step solution:
White light, or the VIBGYOR pattern, is made up of different colours or wavelengths of light. Red has the longest wavelength while violet has the shortest wavelength in these colours.We know that the wavelength of light is inversely proportional to the deviation of light.

The colour with a longer wavelength deviates less, while the colour with a shorter wavelength deviates more. We can claim that the red colour divergence is the smallest and the violet colour deviation is the largest.

The wavelength is proportional to the minimum deviation angle; the shorter the wavelength, the greater the minimal deviation, and vice versa.
\[\lambda = \dfrac{1}{{{\delta _m}}}\]
Here, \[\lambda \] is a wavelength and \[{\delta _m}\] is the angle of minimum deviation.

Therefore, the wavelength for the largest angle of minimal deviation will be the shortest. Because violet has the shortest wavelength, it will be the most diverted.

As a result, the correct answer is option A violet.

Note:As we can see in the spectrum of white light, red is at the top and violet is at the bottom since red deviates the least and violet deviates the most. The variation in the wavelength of colours causes light to disperse. When we incident the spectrum of white light on a prism, the effect is reversed, and we are left with white light. Another example of a spectrum of white light is a rainbow, which occurs when white light is dispersed by water droplets in the atmosphere.