Biot-Savart Law & Circular Coils
A single current carrying loop of wire carrying current I flowing in anticlockwise direction seen from +ve direction and lying in plane is shown in figure. The plot of component of magnetic field (By) at a distance '' (less than radius of the coil) and on plane vs coordinate looks like

Show answer and solution
Answer: (d)
- On the line , , is the radial (sideways) component of the loop's field.
- At (plane of the loop) the field inside the loop is purely along , so .
- The field is along ; field lines spread outwards above the loop ( for ) and converge below it ( for ), and far away.
- So is an odd function of with a positive peak for : answer (d).