Physics - Magnetism Question with Solution | TestHub

A long solenoid with$1000 \mathrm{turns} {\mathrm{m}}^{-1}$has a core material with relative permeability$500$and volume${10}^3{ \mathrm{cm}}^3.$If the core material is replaced by another material having relative permeability of$750$with same volume maintaining same current of$0.75 \mathrm{A}$in the solenoid, the fractional change in the magnetic moment of the core would be approximately$\left(\frac{x}{499}\right).$Find the value of$x.$