Given, number of turns,
n=1000m−1 Electric current, i = 0.75 A
Relative permeability of 1st material
µ1=500 Relative permeability of 2nd material
µ2=750 we know that
µr=1+χ⇒χ =µr−1 For 1st and 2nd material,
χ1=χ1−1=500−1=499 and
χ2=µ2−1=750−1=749 Now, magnetic intensity, M = ni
Let
M1 and
M2 be the magnetisation and
m1 and
m2 be the magnetic moments of material 1st and 2nd.
Using,
=χ1 ...(i)
and
=χ2 ...(ii)
Dividing Eqs. (i) and (ii),
= ...(iii)
We also know that,
i.e
I= = ...(iv)
From Eqs. (iii) and (iv), we get
== Hence, fraction change in magnetic moment,
==(−1) =(−1)= Thus, value of χ is 250.