Interference Pattern Contrast – Rankers Physics

Young's Double Slit Experiment: Practice Problem & Solution

Assertion (A): The best contrast of the interference pattern is obtained when the intensity of the emerging lights from the two slits of the Young's experimental set-up are equal. Reason (R): Intensity is proportional to the square of the amplitude.
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 Young's Double Slit Experiment. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true, as equal intensities (\(I_1 = I_2\)) ensure \(I_{text{min}} = 0\) for maximum contrast.

Reason (R) is true, as intensity \(I propto A^2\). However, (R) does not explain why \(I_1 = I_2\) leads to best contrast.

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