Задача 30471.

At a distance of d = 30 cm, there are two point charges 20 nC and 40 nC. Determine the force F acting on the charge q3 = 12 nC, remote from both charges at the same distance a = 20 cm.

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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