Which set of equations correctly describes Ohm's law and related power in a circuit?

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Multiple Choice

Which set of equations correctly describes Ohm's law and related power in a circuit?

The main idea is how voltage, current, and resistance relate to each other and how power can be expressed in several equivalent ways. The best set uses V = IR, which is Ohm’s law, and then shows power as P = VI and also as P = I^2R and P = V^2/R. That combination is complete and consistent: once you know the voltage and current, or voltage and resistance, you can find all the other quantities using the same relationships. This works because P = VI is the fundamental power relation, and substituting I = V/R or V = IR into it gives the two common forms P = I^2R and P = V^2/R. Having all of these forms together in one set shows how the quantities are interconnected. The other options are incomplete or contain incorrect algebra. For example, rearranging P = VI to I = V/P is wrong (I should be I = P/V). Some sets omit the Ohm’s law link V = IR altogether, or mix up the power expressions (P = I^2/R is not correct; it should be P = I^2R).

The main idea is how voltage, current, and resistance relate to each other and how power can be expressed in several equivalent ways. The best set uses V = IR, which is Ohm’s law, and then shows power as P = VI and also as P = I^2R and P = V^2/R. That combination is complete and consistent: once you know the voltage and current, or voltage and resistance, you can find all the other quantities using the same relationships.

This works because P = VI is the fundamental power relation, and substituting I = V/R or V = IR into it gives the two common forms P = I^2R and P = V^2/R. Having all of these forms together in one set shows how the quantities are interconnected.

The other options are incomplete or contain incorrect algebra. For example, rearranging P = VI to I = V/P is wrong (I should be I = P/V). Some sets omit the Ohm’s law link V = IR altogether, or mix up the power expressions (P = I^2/R is not correct; it should be P = I^2R).

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