An inductor stores energy in its magnetic field when it carries current.
Difficulty
Beginner
Read time
5 min
Prerequisites
Basic algebra and consistent SI units
Source
OpenStax, College Physics 2e, §23.9 (Paul Peter Urone and Roger Hinrichs)Textbook reference retained from the OpenFormulaGraph dataset; adaptation credits and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted the notation, explanations, assumptions, and topic placement, and expanded the numerical check into a worked example.
An inductor stores energy in its magnetic field when it carries current. With constant inductance, the stored energy increases with the square of current and is independent of the sign of that current.
| Symbol | Meaning | Units |
|---|---|---|
| Stored magnetic-field energy | ||
| Inductance | ||
| Current through the inductor |
Estimate energy stored before a switching event.
Compare stored energy at different currents.
An ideal 0.500 H inductor carries 2.00 A. Find its stored magnetic energy.
Textbook reference retained from the OpenFormulaGraph dataset; adaptation credits and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted the notation, explanations, assumptions, and topic placement, and expanded the numerical check into a worked example.
Assumptions
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