An iron rod of the area of cross-section 0.1m2 is subjected to a magnetizing field of 1000 A/m. Calculate the magnetic permeability of the ironmagnet - Physics


An iron rod of the area of cross-section 0.1m2 is subjected to a magnetizing field of 1000 A/m. Calculate the magnetic permeability of the iron rod. [Magnetic susceptibility of iron = 59.9, magnetic permeability of vacuum = 4π x 10-7 S. I. unit]  

An iron rod of the area of cross-section 0.1 m2 is subjected to a magnetizing field of 1000 A/m. Calculate the magnetic permeability of the iron rod.

(χ for iron = 599 , µ0 = 4π × 10-7 SI unit)   


Solution 1

Given:- H= 1000 A/m, χ = 59.9, μ0 = 4π x 10-7 S.I. unit

To find:- Permeability (μ)

Formula:- μ = μ0 (1 + χ)

Calculation:- From formula,

μ = 4π x 10-7 (1 + 59.9)

   = 4 x 3.142 x 10-7 x 60.9

   = antilog [log(4) + log(3.142) + log(60.9)] x 10-7

   = antilog [0.6021 + 0.4972 + 1.7846] x 10-7

   = antilog [2.8839] x 10-7

   = 765.4 x 10-7

∴ μ = 7.654 x 10-5 Wb/A-m

The magnectic permeability of the iron rod is 7.654 x 10-5 Wb/A-m.

Solution 2


H = 1000 A/m, χ = 599,
μ0 = 4π × 10-7 S.I. unit 

To find: Permeability (μ)

Formula: μ = μ0(1 + χ) 


From formula,

μ = 4π × 10-7 (1 + 599)

= 4 × 3.142 × 10-7 × 600 

∴ μ = 7.54 × 10-4 Hm-1  

The magnetic permeability of the iron rod is 7.54 × 10-4 Hm-1

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