Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Permeability of free space, denoted as $\mu_0$, is a physical constant that describes how magnetic fields interact with the vacuum. It is essential in calculating the strength of magnetic fields generated by currents.
5 Must Know Facts For Your Next Test
The value of permeability of free space ($\mu_0$) is exactly $4\pi \times 10^{-7}$ T·m/A (tesla meter per ampere).
$\mu_0$ appears in Ampere's Law, which relates magnetic field and electric current.
In the SI system, $\mu_0$ helps define the relationship between electric currents and magnetic fields.
$\mu_0$ is used to calculate the inductance of coils and solenoids in circuits.
The permeability of free space is a fundamental parameter in Maxwell's equations.
A fundamental law stating that for any closed loop path, the sum of the length elements times the magnetic field in the direction of those elements equals $\mu_0$ times the current enclosed by the loop.
A set of four equations that describe how electric charges produce electric fields, how electric currents produce magnetic fields, and how changing magnetic and electric fields propagate through space.