1000 turns per meter are wound over a Rowland ring of ferromagnetic material. On passing a current of 2 ampere in the coil, a magnetic field of 10 Wb/m2 is produced in it.

The magnetising force generated in the material will be :

1.2  x 10–3 A/m 2.6 x 10–3 A/m 2.6 x 10–4 A/m 2 x 103 A/m

2 x 103 A/m

$ H = \frac{NI}{2\pi r} = nI = 2\times 10^3A/m$