$N$ equally spaced charges each of value $q$, are placed on a circle of radius $R$. The circle rotates about its axis with an angular velocity $\omega$ as shown in the figure. A bigger Amperian loop B encloses the whole circle where as a smaller Amperian loop A encloses a small segment. The difference between enclosed currents, $\mathrm{I}_{\mathrm{A}}-\mathrm{I}_{\mathrm{B}}$, for the given Amperian loops is