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Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): In Young's double slit experiment, the fringes produced by red light are closer as compared to those produced by blue light.
Reason (R): The fringe width is directly proportional to the wavelength of light.
In the light of the above statements, choose the correct answer from the options given below.

Asked in JEE Main 22nd Jan 2nd Shift 2025 · Fringe width and fringe position

• (1) (A) is true but (R) is false.
• (2) Both (A) and (R) are true and (R) is the correct explanation of (A).
• (3) (A) is false but (R) is true.
• (4) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Step-by-step solution

Why the other options are wrong

• (1) Thinks red has a shorter wavelength than blue.
• (2) Accepts A without checking that red has the longer wavelength.
• (4) Accepts A and treats R as unrelated.

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