Magnetic field of a uniformly conducting strip
= Magnetic field of a uniformly conducting strip
{title2=$B(z)$}
For an infinitely long thin strip of width $w$ carrying uniform longitudinal current $I$, the <magnetic field> a perpendicular <distance> $z>0$ above its centre has magnitude $B=\mu_0I\arctan(w/(2z))/(\pi w)$. Its near-sheet limit is $\mu_0I/(2w)$ and its distant line-current limit is $\mu_0I/(2\pi z)$.