Задача 31390.

The electric field created by a metal sphere of radius 18 cm, having a surface charge density of 2 SCLC / m ^ 2. Find: the energy of the electric field in a volume of dielectric constant of 2, limited to this sphere and concentric with the spherical surface, it is 2 times larger radius; charge density induced on the surface of the dielectric.

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