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Which equation is used to define resistance?

Correct answer: C. Potential difference = current x resistance

  • A. Energy = (current)² x resistance x time
  • B. Power = (current)² x resistance
  • C. Potential difference = current x resistance
  • D. Resistivity = resistance x area + length

Explanation

Resistance (R) is defined as the ratio of the potential difference (V) across a component to the current (I) flowing through it. This relationship is a rearrangement of Ohm's Law, R = V/I.

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About Current Electricity

Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.

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