电功率计算器 — 公式

Electrical Power

Electrical power is the rate of energy transfer in an electric circuit.

Three Equivalent Forms

P = V * I (voltage times current)

P = I² * R (current squared times resistance)

P = V² / R (voltage squared divided by resistance)

All three yield the same result when V, I, and R satisfy Ohm's law.

计算示例

A 120 V circuit drawing 5 A through a 24 ohm load.

  1. P = V * I = 120 * 5 = 600 W
  2. P = I² * R = 25 * 24 = 600 W
  3. P = V² / R = 14400 / 24 = 600 W