Correct Answer - Option 4 : 16.67
Concept:
Magnetic field strength or field intensity (H) is the amount of magnetizing force.
Magnetic flux density (B) is the amount of magnetic force induced on the given body due to the magnetizing force H.
The relation between B and H is,
B = μH
Where,
μ = μ0 μr = Permeability of the material
μ0 = Absolute permeability = 4π x 10-7 H/m
μr = relative permeability
Calculation:
Given-
I = 2350 A/m , B = 3.142 mWb/m2
B = μ0 (I + H)
\((I+H)=\frac{3.14\times10^{-3}}{4 \times 3.14\times10^{-7}}\)
H = 150
We know that,
B = μH
\(μ=\frac{3.14\times10^{-3}}{150}\)
μ = 20 x 10-6
The relative permeability of the material is
∵ μ = μ0μr
\(μ_r=\frac{20\times10^{-6}}{4\times3.14\times10^{-7}}\)
μr ≈ 16.67