Задача 40428.

A ball of mass 16 g is suspended on a non-conducting thread and oscillates with a period of 1 s. The ball was given a charge and placed in a uniform electric field with a strength of 30 V/m, directed vertically. The oscillation period became 0.8 s. Find the charge of the ball.

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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