Physics
Electrical Power
Calculate electrical power in a resistive circuit.
P = VI = I²R = V²/R
Formula Explanation
These equivalent formulas apply to a resistor obeying Ohm law under the relevant conditions.
Variables Explained
P = Power; V = Voltage; I = Current; R = Resistance.
Solved Example
A 12 V device draws 2 A. Find power.
P = 12 × 2 = 24 W.