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# 4.6: Dissipation of Energy

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When current flows through a resistor, electricity is falling through a potential difference. When a coulomb drops through a volt, it loses potential energy 1 joule. This energy is dissipated as heat. When a current of $$I$$ coulombs per second falls through a potential difference of $$V$$ volts, the rate of dissipation of energy is $$IV$$, which can also be written (by making use of Ohm’s law) $$I^2R \text{ or }V^2/R$$.

If two resistors are connected in series, the current is the same in each, and we see from the formula $$I^2R$$ that more heat is generated in the larger resistance.

If two resistors are connected in parallel, the potential difference is the same across each, and we see from the formula $$V^2/R$$ that more heat is generated in the smaller resistance.

4.6: Dissipation of Energy is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jeremy Tatum via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.