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:

For best contrast in an interference pattern, the amplitudes of the interfering waves must be equal, implying equal intensities. Intensity \(I\) is proportional to the square of the amplitude \(A\), i.e., \(I \propto A^2\). Thus, equal intensities lead to maximum contrast.

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Similar Practice Questions

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