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Which of the following are true for a single slit diffraction? (A) Width of central maxima increases with increase in wavelength keeping slit width constant. (B) Width of central maxima increases with decrease in wavelength keeping slit width constant. (C) Width of central maxima increases with decrease in slit width at constant wavelength. (D) Width of central maxima increases with increase in slit width at constant wavelength. (E) Brightness of central maxima increases for decrease in wavelength at constant slit width.

1. (1) A, D, E only
2. (2) A, D only
3. (3) B, D only
4. (4) B, C only

Correct answer: (1) A, D, E only

Solution

Option A is correct because increasing the wavelength causes the diffraction pattern to spread out, resulting in a wider central maximum. Option D is also correct since increasing the slit width reduces the diffraction effect, leading to a narrower central maximum. Option E is true because a shorter wavelength increases the intensity of the central maximum, making it appear brighter.

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