How is wattage calculated in an electrical circuit?

Wattage, or power, in an electrical circuit is calculated by multiplying voltage (measured in volts) by current (measured in amps). This relationship is derived from the fundamental principles of electricity, specifically Ohm's Law and the definition of power. The formula for power (P) can be expressed as:

P (watts) = V (volts) × I (amps)

This formula illustrates that the total power consumed in an electrical circuit is the product of the voltage across the circuit and the current flowing through it. Thus, knowing either the voltage or current allows one to calculate wattage effectively.

The other choices involve different relationships. Resistance multiplied by voltage actually relates to current in the context of Ohm's Law but does not directly give wattage. Voltage divided by current provides resistance, and current divided by resistance gives voltage, neither of which directly calculates power. Therefore, the multiplication of volts and amps is the correct approach to determine wattage in an electrical circuit.