Some equipotential surfaces of the magnetic scalar potential are shown in the figure. Magnetic field at a point in the region is
10–4 T
2 x 10–4 T
0.5 x 10–4 T
None of these
∆x=10 sin300=10 cm2=10-12 mslope=0.1 x 10-410-12=2 x 10-4 T