Задача 31518.

Points A, B, C and D are on the same line. And AB = BC = CD = 10 cm. At points A and C are situated charges + 2 * 10 ^ -6 C and the -15 * 10 ^ -6 Cl. Determine the strength and potential of the field at points B and D.

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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