Задача 31606.

In a homogeneous magnetic field with induction B = 5 mT, a slightly divergent beam of electrons with velocity v = 6 Mm / s emerges from a certain point O in the direction of the field. Determine the distance l from the point O to the nearest point F, at which the trajectories of all the beam electrons intersect. Pictures

A detailed solution with a brief description of the condition, formulas and laws used in the solution, the derivation of the formula and the answer.
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