The colored light that refracts most while passing through a prism is

CONCEPT

In normal dispersion, a transparent material’s refractive index increases as the wavelength of visible light decreases. For the same prism and angle of incidence, a larger refractive index produces a larger angular deviation.

APPLICATION

1. Compare the offered individual colors by wavelength: violet has the shortest wavelength, followed by blue, while yellow has a longer wavelength.

2. Therefore the prism’s refractive index is greatest for violet among these colors.

3. Since prism deviation increases with refractive index, violet light undergoes the greatest deviation.

CROSS-CHECK / CONTRAST

• Yellow: its longer wavelength gives a smaller refractive index and deviation than the shorter-wavelength colors.

• Blue: it deviates more than yellow but less than violet.

• More than one of the above: normal dispersion gives different deviations to these different wavelengths, not a tie for the greatest deviation.

• None of the above: violet is included among the listed colors.

Result: violet light refracts, or deviates, the most in the prism.