Задача 31232.

Between two horizontal planes, oppositely charged and located 5 mm from each other, a 20 nanogram drop of oil is in equilibrium. Find the number of excess electrons on this droplet, the potential difference between the planes is 2 kV. Wednesday air.

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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