Which expression gives the magnitude of the magnetic field produced by a long

PHYSICS · Single correct · AP · Physics 2: Algebra-based · Magnetism and Electromagnetism · Magnetism and Electromagnetism

Problem

Which expression gives the magnitude of the magnetic field produced by a long, straight wire that carries a steady current

I

at a point located a perpendicular distance

r

from the wire in free space? (a)

B=\dfrac{\mu_{0} I}{\pi r}

(b)

B=\dfrac{\mu_{0} I}{4\pi r}

(c)

B=\dfrac{\mu_{0} I}{2\pi r}

(d)

B=\dfrac{\mu_{0} I}{2 r}