34. Wave Optics

(II) Derive the law of reflection—namely, that the angle of incidence equals the angle of reflection from a flat surface—using Huygens’ principle for waves.

Show that the angular full width at half maximum of the central peak in a double-slit interference pattern is given by ∆θ = λ/2d if λ ≪ d.

(III) (a) Consider three equally spaced and equal-intensity coherent sources of light (such as adding a third slit to the two slits of Fig. 34–12). Use the phasor method to obtain the intensity as a function of the phase difference δ (Eq. 34–4). (b) Determine the positions of maxima and minima.

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(III) Consider three equally spaced and equal-intensity coherent sources of light (such as adding a third slit to the two slits of Fig. 34–12). (b) Determine the positions of maxima and minima.

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(III) Consider three equally spaced and equal-intensity coherent sources of light (such as adding a third slit to the two slits of Fig. 34–12). (b) Determine the positions of minima.

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