Electricity & Magnetism
Advanced

Field of a Straight Wire

Magnetic field around a long straight wire.

Formula

B=μ0I2πrB = \frac{\mu_0 I}{2\pi r}

Variables

\mu_0Permeability
ICurrent
rDistance

Did You Know?

Oersted discovered by accident in 1820 that a current deflects a compass, uniting electricity and magnetism.

magnetic fieldwireampere