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Assume that each iron atom has a permaan...

Assume that each iron atom has a permaanent magnetic moment equal to 2 Bohr magnetons `(1 Bohr magneton equals 9.27 xx 10^(-24) A m^2)`. The density of atoms in iron is `8.52 xx 10^28 atoms` ` m^(-3)`. (a) Find the maximum magnetization `I` in a long cylinder of iron. (b) Find the maximum magnetic field `B` on the axis inside the cylinder.

Text Solution

Verified by Experts

Here `f=8.52xx10^(28) atoms//m^(3) For maximum I,`
`Let us consider the number of atoms present in 1 M^(3) of volume `
`M per atom =2xx9.27xx10^(-24) A-m^(2)`
`I=( net M)/V`
`=2xx9.27xx10^(-24)xx8.52xx10^(28)`
`=1.58xx10^(5) A//m.`
`so, B=4 pi xx10^(-7)xx1.58xx10^(5)`
`~~19.8xx10^(-1)=2.0 T`.
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