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Electronics

Ohm’s law & power

Calculate current and dissipated power for a resistive load.

Inputs

Example values

Min 0 · max 100,000

Greater than 0 · max 1,000,000,000

Point or comma for decimals.

Results

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The calculation

I = V / R
P = V² / R

Assumptions & limits

Use DC voltage or RMS voltage across a pure resistance. A loudspeaker’s frequency-dependent impedance cannot generally be replaced by its DC resistance for AC power calculations.

Background: Electric circuits · OpenStax University Physics
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