Задача 31550.

Flat air condenser with the distance between the plates 4 cm charged to a potential difference of 300 V and disconnected from the voltage source. Then the condenser to half its length vdvinuli glass plate thickness of 4 cm (e = 7). To determine the density of free charges on the half capacitor plate, which is in contact with the insulator.

Detailed solution with a short recording conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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