Задача 30608.

On the extension of the axis of a thin straight rod, uniformly charged with a linear charge density of 400 nC / cm, at a distance of 30 cm from the end of the rod, there is a point charge of 20 μC. The other end of the rod goes to infinity. Determine the force of interaction between the rod and the point charge.

Detailed solution with a short recording of the conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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