Which expression is Ohm's law?

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Multiple Choice

Which expression is Ohm's law?

Ohm's law describes how voltage, current and resistance relate: voltage equals current times resistance. This direct link shows that if you know the current flowing through a conductor and its resistance, you can find the voltage across it using V = I × R. It also makes clear why the other forms aren’t the law: I = P / V and P = V × I describe electrical power, not the voltage–current–resistance relationship; and V = R / I would give the wrong unit relation (volts not matching ohms per amp). The correct expression, V = I × R, is the standard way Ohm's law is written.

Ohm's law describes how voltage, current and resistance relate: voltage equals current times resistance. This direct link shows that if you know the current flowing through a conductor and its resistance, you can find the voltage across it using V = I × R. It also makes clear why the other forms aren’t the law: I = P / V and P = V × I describe electrical power, not the voltage–current–resistance relationship; and V = R / I would give the wrong unit relation (volts not matching ohms per amp). The correct expression, V = I × R, is the standard way Ohm's law is written.

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