Задача 31296.

Charge with a linear density of 3 × 10 -6 C / m uniformly distributed over the thin half-rings, the center of curvature of which is a point charge q = 5 * 10 ^ -11 Kl. The strength of the interaction between a point charge and charged half-ring is equal to 5 x 10 -5 N. Find the radius of the half-ring.

Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.
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