# A magnetising field of 1600 Am^(-1) produces a magnetic flux of 2.4 × 10^(-5) weber in a bar of iron…

Q: A magnetising field of 1600 Am-1 produces a magnetic flux of 2.4 × 10-5 weber in a bar of iron of cross section 0.2 cm2. Calculate permeability and susceptibility of the bar.

Sol: Magnetic induction $\large B = \frac{\phi}{A} = \frac{2.4 \times 10^{-5}}{0.2 \times 10^{-4}}$

B = = 1.2 Wb/m2

(i) Permeability, μ = B/H = 1.2/1600 = 7.5 × 10-4  TA-1m

(ii) As μ = μ0 (1 + χ) then

Susceptibility, $\large \chi = \frac{\mu}{\mu_0} – 1$

$\large \chi = \frac{7.5 \times 10^{-4}}{4\pi \times 10^{-7}} – 1$

= 596.1