Question 11:
easy
The magnetic moment produced in a substance of \(1\text{ gm}\) is \(6 \times 10^{-7}\text{ A-m}^2\). If its density is \(5\text{ gm/cm}^3\), then the intensity of magnetisation in \(A/m\) will be:
Intensity of magnetisation is \(I = \frac{M}{V} = \frac{M\rho}{m}\). Given \(m = 1\text{ gm}\), \(M = 6 \times 10^{-7}\text{ A-m}^2\), \(\rho = 5 \times 10^3\text{ kg/m}^3\). Thus \(I = \frac{6 \times 10^{-7} \times 5 \times 10^3}{10^{-3}} = 3.0\text{ A/m}\).