A circular loop of one turn carries a current of 5.00 A. If the magnetic field B at the centre is 0.200 mT, find the radius of the loop.

Explanation

Here n=1 B at centrre O `=(mu_oi)/(2R)`
`rArr 0.2xx10^(-3) = (4pixx10^(-7)xxS)/(2R)`
`rArr R = 1.57 cm`.