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Qmechanic
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why Why electric charge does not gain net energy in closed circuit?

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Yevgeniy P
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why electric charge does not gain net energy in closed circuit

In a text book, when they calculate power dissipated in a closed circuit, they use circuit with a battery and one resistor. Idealized positive charge travels from + terminal (point B) of the battery then through resistor, then to the - terminal (point A) of the battery. Then battery pushes the charge back to the + terminal and the cycle begins again. The calculation based on the assumption that as the charge travels from point A back to point A, its net gain of energy is 0, that is the potential energy given to it by the battery is totally spent by the resistance in the circuit (in particular at the resistor if considering idealized wire).

Somehow I fail to see this as obvious. Yes, when the charge arrives back to point A it will have the same potential energy as when it started (in the example in the book point A is grounded so potential is 0). But what prevents it from having more kinetic energy then when it started? What prevents the charges from being accelerated?

I understand that resistance acts against acceleration, like friction force. But what makes those forces (electrical and resistance) and corresponding energy gains/losses exactly balanced?