Write the formula for the magnetic field at the centre of a circular current-carrying loop.

(N/A) For a circular loop of radius $R$ carrying a current $I$,the magnetic field $B$ at its centre is given by the formula:
$B = \frac{\mu_0 I}{2R}$
Where:
$B$ is the magnetic field in Tesla $(T)$,
$\mu_0$ is the permeability of free space $(4\pi \times 10^{-7} \ T \cdot m/A)$,
$I$ is the current in Amperes $(A)$,
$R$ is the radius of the loop in meters $(m)$.