Задача 30486.

The negatively charged surface of the heated filament electron leaves a speed of 20 m / s. What speed, he will be at a distance of R = 2 cm from its center? The linear charge density of the filament 2 x 10 -9 C / m, the radius of the thread of 0.5 mm.

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