Which term describes the rate at which electrical energy is consumed or transformed in a circuit?

Which term describes the rate at which electrical energy is consumed or transformed in a circuit?

• A. Voltage
• B. Current
• C. Power
• D. Resistance

Answer: (C)

Power is the rate at which electrical energy is consumed or transformed in a circuit, and it is measured in watts. In circuits, power equals voltage times current (P = V × I). If you know the resistance, you can also use P = I²R or P = V²/R. This shows why power is the right term: it directly describes how much energy per second is being used or converted into light, heat, motion, and so on. For example, a 60-watt lamp at 120 volts draws about 0.5 A of current (I = P/V = 60/120 = 0.5). The other quantities describe different ideas: voltage is the driving potential, current is the flow of charge, and resistance is how much a component opposes that flow.

Power is the rate at which electrical energy is consumed or transformed in a circuit, and it is measured in watts. In circuits, power equals voltage times current (P = V × I). If you know the resistance, you can also use P = I²R or P = V²/R. This shows why power is the right term: it directly describes how much energy per second is being used or converted into light, heat, motion, and so on. For example, a 60-watt lamp at 120 volts draws about 0.5 A of current (I = P/V = 60/120 = 0.5). The other quantities describe different ideas: voltage is the driving potential, current is the flow of charge, and resistance is how much a component opposes that flow.