White Light through Prisms – Rankers Physics

Refraction by Prism: Practice Problem & Solution

Assertion (A): When white light passes successively through two identical prisms, one inverted with respect to other, then in emergent side, again white light is obtained. Reason (R): Prism has no ability to create colour but it only separates the colours already present in white light.  
(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(3) (A) is true but (R) is false
(4) 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:

Assertion (A) is true; the second inverted prism recombines the dispersed light back into white light. Reason (R) is true; prisms only disperse existing colours, they do not create new ones. Reason (R) correctly explains Assertion (A).

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