A particle with a positive charge q and velocity v moves towards a rectangular strip so that that its velocity vector forms an angle α with the normal of the strip. The thickness of the strip is d and on it is located a homogeneous z-directional magnetic field with an induction B (from the plane of the paper directed towards us). For what maximal falling angle αmax does the particle still go through the magnetic field? It is known that the particle that enters the strip perpendicularly would go through the strip.
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