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Question
The magnetic susceptibility of annealed iron at saturation is 4224. Find the permeability of
annealed iron at saturation. (μ0 = 4Π × 10−7 SI unit)
Solution
χ = 4224
∴ μ = μ0 (1 + χ)
= 4π × 10−7 (1 + 4224)
= 16900 π × 10−7
= 169 × 3.142 × 10−5
= [log (169) + log (3.142)] × 10−5
= [2.2279 + 0.4972] × 10−5
= antilog (2.7251)] × 10−5
= 531 × 10−5
= 5.31 × 10−3 Hm−1
The permeability of annealed iron at saturation is 5.31 × 10−3 Hm−1.
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