Задача 31653.

With an external resistance of 3.75 ohms, a current of 0.5 A flows in the circuit, when another resistance of 1, 0 ohms was introduced into the circuit in series with the first resistance, and the current became 0.4 A. Find the EMF and the internal resistance of the source, short-circuit current.

A detailed solution with a brief entry of the condition, formulas and laws used in the solution, the derivation of the formula and the answer.
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