Which symbol is commonly used to denote electrical power?

• A. P
• B. I
• C. V
• D. R

Answer: (A)

In electrical circuits, power is the rate at which electrical energy is transferred or used. The symbol used to denote this quantity is P, which you’ll see in formulas like P = VI for direct current, where V is voltage and I is current. This shows power as the product of voltage and current. You can also express the same quantity as P = I^2R or P = V^2/R, depending on which variables you know. That flexibility reinforces why P is the standard symbol for power.

The other symbols stand for different quantities: I represents current, V represents voltage, and R represents resistance. Power is a separate concept, and its unit is the watt (W). For example, with 120 V and 2 A, the power is 240 W.

So the symbol commonly used to denote electrical power is P.