This measures power, the rate at which electrical energy is consumed or transformed into energy such as light or heat.

This measures power, the rate at which electrical energy is consumed or transformed into energy such as light or heat.

• A. Volts
• B. Ampere
• C. Ohm
• D. Watt

Answer: (D)

Power is the rate at which energy is used or transformed in a circuit, and the unit that directly measures that rate is the watt. A watt represents one joule of energy per second, and in electrical terms it ties together how much energy is being pushed through (voltage) and how much current is flowing, since P = V × I. The other terms describe what drives or resists that energy flow: volts are electrical potential difference, amperes measure current, and ohms measure resistance. A device’s power rating, like a light bulb’s wattage, tells you how quickly it converts electrical energy into light and heat.

Power is the rate at which energy is used or transformed in a circuit, and the unit that directly measures that rate is the watt. A watt represents one joule of energy per second, and in electrical terms it ties together how much energy is being pushed through (voltage) and how much current is flowing, since P = V × I. The other terms describe what drives or resists that energy flow: volts are electrical potential difference, amperes measure current, and ohms measure resistance. A device’s power rating, like a light bulb’s wattage, tells you how quickly it converts electrical energy into light and heat.