Задача 31489.

Point charge Q1 = 2 nC, Q2 = -1 nC, Q3 = -1 nC located on the plane in the lattice sites to the cell in the form of a square with sides of 0.1 m. The lattice sites, which are referred to the charges set radius vectors r1 = (0,0), r2 = (a, 0), r3 = (- a, 0). The remaining nodes are no charges. Determine the dipole moment of the system of charges and their potential energy in an external electric field E = (0, -100) V / m.

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