Physical Sciences
Electromagnetism
1827
BeginnerOhm's Law
Voltage across a conductor equals current times resistance.
By Georg Ohm
Physical Sciences
Ohm's Law
1827 · Georg Ohm
Human Reviewed
84%
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Story PortalWho discovered this?Discover how Georg Ohm and others shaped this equation.Visual PortalWhat does it look like?See the equation come alive in the Visual Studio.Machine PortalWhere is it used?Explore machines powered by this equation — circuit design.Math PortalWhat does it derive from?Trace the mathematical lineage from coulombs law.Future PortalWhere is it going?Neuromorphic chips
Why it matters: Enabled the electrical age—power grids, electronics, and computing.
Discoverers: Georg Ohm (1827)
What does it mean?
Voltage across a conductor equals current times resistance.
Why should I care?
Enabled the electrical age—power grids, electronics, and computing.
Equation Compass
North — Prerequisites
West — History
East — Applications
South — Derivations
Variables & Units
| Symbol | Name | Unit | Meaning |
|---|---|---|---|
| Voltage | V | Potential difference | |
| Current | A | Electric current | |
| Resistance | Ω | Electrical resistance |
Worked Example
12 V battery, 4 Ω resistor → I = 3 A.
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Ohm's Law
Real-world impact
Power grids & circuits
V = IR wires civilization — from wall sockets to smartphone processors.
Photo: Unsplash — printed circuit board
Voltage across a conductor equals current times resistance.
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