Light Dispersion at Plane Surface – Rankers Physics

Refraction by Prism: Practice Problem & Solution

Assertion (A): Splitting of light into its component colours is possible in refraction at plane surface of two media. Reason (R): On each refraction dispersion is possible but in prism at both surface dispersion is in same direction so it is clearly seen.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Refraction by Prism. Understanding the underlying formula is key to arriving at the correct answer below:

Dispersion, the splitting of light into its constituent colors, occurs during refraction because the refractive index of a medium depends on the wavelength of light. This effect is present at any plane refractive surface. In a prism, the refractions at both surfaces cause deviations for different colors that add up in the same direction, making the overall dispersion more noticeable. Both A and R are true, and R explains A.

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