Consider the Fraunhofer diffraction pattern for eight very narrow parallel slits under monochromatic illumination.

(a) Sketch the resulting irradiance distribution.

(b) Explain why the first minimum occurs, from a phasor perspective.

(c) Why is the electric field zero midway between principal peaks?

(d) What does the phasor diagram of the field amplitude look like for the second minimum (measured from the zeroth principal maximum)?

(e) What are the angles between successive phasors at each minimum considered above?