Which equation correctly relates voltage, current, and resistance according to Ohm's Law?

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Multiple Choice

Which equation correctly relates voltage, current, and resistance according to Ohm's Law?

Ohm’s Law shows how voltage, current, and resistance relate in a conductor: the voltage across a component equals the current through it times its resistance. This means doubling either the current or the resistance will double the voltage drop, keeping the relationship linear for a given resistance. The units line up cleanly: volts equal amperes times ohms. If you know voltage and resistance, you get current by I = V / R; if you know current and resistance, you get voltage by V = I × R. The other forms don’t fit: V = R / I would make voltage depend on resistance per current; I = V × R would give current in volt-ohms, which isn’t a current unit; P = V × I × R isn’t the correct expression for electrical power.

Ohm’s Law shows how voltage, current, and resistance relate in a conductor: the voltage across a component equals the current through it times its resistance. This means doubling either the current or the resistance will double the voltage drop, keeping the relationship linear for a given resistance. The units line up cleanly: volts equal amperes times ohms. If you know voltage and resistance, you get current by I = V / R; if you know current and resistance, you get voltage by V = I × R. The other forms don’t fit: V = R / I would make voltage depend on resistance per current; I = V × R would give current in volt-ohms, which isn’t a current unit; P = V × I × R isn’t the correct expression for electrical power.

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