Electromagnetic Waves and Wave Optics: Single-Slit Width and Minima Count MCQ

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Single-Slit Width and Minima CountHardQuestion 20229

Question

A single slit of width 0.2 mm is illuminated by λ = 500 nm. Angle of first diffraction minimum is:

2.5 mrad

a sinθ = λ → sinθ = λ/a = 500×10⁻⁹/0.2×10⁻³ = 2.5×10⁻³. For small angles sinθ ≈ θ = 2.5 mrad.