Задача 31551.

To determine the energy density of the electric field created in vacuo uniformly charged long straight filament with a linear density of charge 3 × 10 -8 C / m, at a point located at a distance of 10 cm from the center of the filament.

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