If the voltage is 120 V and the current is 10 A, what is the power in watts using the formula W = V x A?

• A. 120 W
• B. 1200 W
• C. 12 W
• D. 100 W

Answer: (B)

Power in a circuit is found by multiplying voltage by current: P = V × I. With 120 V and 10 A, you get 120 × 10 = 1200 watts. The idea is that volts tell you how much electrical potential each ampere has to push, and multiplying by the number of amperes gives how much energy per second is being transferred. The other numbers would come from different currents (for example, 1 A would give 120 W, 0.1 A would give 12 W, and about 0.833 A would give 100 W), but with the given values the product is 1200 W.