Science & Energy
Ohm's Law
Updated 2025-08-04
Definition
The fundamental relationship in electrical circuits: V = I × R, where voltage (V) equals current (I) times resistance (R). Power dissipation follows: P = V × I = I²R. Named for German physicist Georg Ohm, who published the relationship in 1827. Every electrical calculation, from LED current-limiting resistors to whole-house load balancing, starts here. A 12-volt car battery driving a headlight with 3 ohms of resistance produces 4 amps of current and 48 watts of power.
Primary source: NIST ampere definition
Related Calculators
- Ohm's Law Calculator - Calculate voltage, current, resistance, and power using Ohm's Law (V = IR).
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