Solving a problem in physics section 25 point 57 optics

Solving a problem in physics section 25 point 57 optics

57. The diffraction pattern is observed at a distance of 0.8 m from the point source of monochromatic light (λ = 0,625 m). Halfway between the light source and the screen is placed a diaphragm with a circular hole. For what the smallest diameter hole center of the diffraction pattern is dark?

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)