Electric field is the electric force per unit test charge.
Difficulty
Intermediate
Read time
5 min
Prerequisites
Basic algebra, consistent units, and the stated model assumptions
Source
OpenStax, College Physics 2e, §18.4 (Paul Peter Urone and Roger Hinrichs)OpenFormulaGraph equation reference; FormuLab adaptation details and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted wording, notation, applicability conditions and topic placement, and expanded the numerical check into a worked example.
Electric field is the electric force per unit test charge. The vector force reverses direction for a negative charge; scalar components must use a consistent sign convention.
| Symbol | Meaning | Units |
|---|---|---|
| Electric Field | ||
| Force | ||
| Electric charge |
Infer a field component from an electric force.
Relate a field to the force on a known charge.
A +4.00 µC test charge experiences an electric force of +0.00200 N along an axis. Find that component of electric field.
OpenFormulaGraph equation reference; FormuLab adaptation details and license are provided below.
Adapted from OpenFormulaGraph, under CC BY 4.0.
FormuLab adapted wording, notation, applicability conditions and topic placement, and expanded the numerical check into a worked example.
Assumptions
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