Solving a problem in physics section 19 point 60 optics

Solving a problem in physics section 19 point 60 optics

60. A parallel beam of electrons moving with the same velocity υ = 1 mm / s, normally incident on the diaphragm with a long slit width a = 1 mm. Passing through the gap, the electrons are scattered and form a diffraction pattern on a screen located at a distance L = 50 cm from the slot and parallel to the plane of the diaphragm. Determine the distance x between the first diffraction minima

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