Задача 31285.

Flat air capacitor C = 10 pF charged to a potential difference U 1 = 500 V. After disconnecting the capacitor from the voltage source the distance between the capacitor plates was increased 3-fold. To determine: 1) the potential difference across the capacitor plates after razdvizheniya; 2) the work of external forces on the extendable plates.

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