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

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

Correct answer: (A) is false but (R) is true.

Solution

The assertion is incorrect because red light has a longer wavelength than blue light, which means its fringes are actually wider apart, not closer. The reason is correct as it accurately states that fringe width is directly proportional to the wavelength.

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