Physics

Problem

Which one of the following expressions represents the magnitude of the magnetic field at the centre of a single circular loop of radius

R

carrying a steady current

I

in free space? a)

B=\dfrac{\mu_0 I}{2\pi R}

B=\dfrac{\mu_0 I}{R}

B=\dfrac{\mu_0 I}{2R}

B=\dfrac{\mu_0 I}{4\pi R}