Which expression correctly defines electrical power in a DC circuit?

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Multiple Choice

Which expression correctly defines electrical power in a DC circuit?

Power in a DC circuit is the rate at which electrical energy is transferred or used, and it equals voltage multiplied by current. This direct relationship, P = V × I, shows how the driving force (voltage) and the flow of charges (current) determine how much energy per second is moved or consumed. You can derive other equivalent forms from Ohm’s law for resistive loads: P = I²R and P = V²/R. For example, with 12 volts across a component carrying 2 amperes, the power is 24 watts. The other expressions don’t represent power: I × R gives voltage, V × R isn’t the standard power form, and V ÷ I gives resistance, not power.

Power in a DC circuit is the rate at which electrical energy is transferred or used, and it equals voltage multiplied by current. This direct relationship, P = V × I, shows how the driving force (voltage) and the flow of charges (current) determine how much energy per second is moved or consumed. You can derive other equivalent forms from Ohm’s law for resistive loads: P = I²R and P = V²/R. For example, with 12 volts across a component carrying 2 amperes, the power is 24 watts. The other expressions don’t represent power: I × R gives voltage, V × R isn’t the standard power form, and V ÷ I gives resistance, not power.

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