Electricity

In a parallel circuit, adding more paths for current reduces the overall opposition to flow, meaning the total resistance is always less than that of the smallest individual resistor. Option A is incorrect because summing the individual resistances calculates the total resistance of a series circuit, not a parallel one.

The total resistance in the circuit is the sum of the external resistance and the internal resistance, which equals 6 ohms. Using Ohm's law, dividing the 12 V EMF by this total resistance of 6 ohms yields a current of 2 A. Option C is incorrect because it fails to account for the internal resistance of the battery.

According to Ohm's law, electrical resistance is defined as the ratio of potential difference to current, which makes R = V / I the correct formula. A diagram for this topic isn't available yet — the worked example below walks the same reasoning step by step.

• !Option A is incorrect because multiplying voltage by current yields electrical power, whilst option C incorrectly inverts the relationship.
• !Option A is incorrect because summing the individual resistances calculates the total resistance of a series circuit, not a parallel one.
• !Electromotive force (EMF) represents the energy transferred per unit charge, which is measured in joules per coulomb, commonly known as volts.
• !Option C is incorrect because it fails to account for the internal resistance of the battery.

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