Electrical Power (P = I²R)
Also known as I²R losses · copper loss
Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!
Learning zone
Joule heating grows with the square of the current: triple the current and a wire dissipates nine times the heat. This is why power grids transmit at hundreds of kilovolts — stepping the voltage up cuts the current for the same delivered power, slashing I²R losses in the lines. Solving for I takes the principal positive square root, the current's magnitude.
Electrical Power (P = I²R)
Where
- = Power
- = Current
- = Resistance
Missing one of these? Work it out first, then come back
- Power — Electrical Power (P = VI), Electrical Power (P = V²/R)
- Current — Ohm's Law, Electrical Power (P = VI)
- Resistance — Ohm's Law, Electrical Power (P = V²/R)