Задача 30674.

At the corners of a square with a side of 10 cm there are four charges q1=20 nC, q2=15 nC, q3=-25 nC, q4=5 nC. How much work needs to be done on a charge Q=10 nC to move it from infinity to the center of the square.

Detailed solution with a brief record of the conditions, formulas and laws used in the solution, derivation of the calculation formula and answer.
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