Question

A magnetizing field of 5000 A/m produces a magnetic flux of 4 x 10^-5 Wb in an iron rod of cross-sectional area 0.4 cm². The permeability of the rod in Wb/A-m, is ______.

विकल्प

• 4 × 10^-6

• 1 × 10^-3

• 2 × 10^-4

• 3 × 10^-5

Answer 1

A magnetizing field of 5000 Alm produces a magnetic flux of 4 x 10^-5 Wb in an iron rod of cross-sectional area 0.4 cm². The permeability of the rod in Wb/A-m, is 2 × 10^-4.

Explanation:

Given, magnetising field, H = 5000 A/m

Magnetic flux, Φ = 4 × 10^-5 Wb

Cross-sectional area, A = 0.4 cm² = 4 x 10^-5 m²

∴ Permeability of rod,

`mu = "B"/"H" = phi/"AH"   ...[phi = "BA" => "B" = phi/"A"]`

`= (4 xx 10^-5)/(4 xx 10^-5 xx 5000)`

`= 2 xx 10^-4  "Wb"//"A-m"`