Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
A physical constant denoted by μ₀, representing the ability of free space to allow magnetic field lines to pass through it. It has a value of approximately 4π x 10⁻⁷ T·m/A.
Related terms
Magnetic Field Strength: The force experienced by a unit positive test charge moving perpendicular to magnetic field lines.
Magnetic Flux Density (B-field): A measure of the strength and directionality of a magnetic field at any given point.