The intensity of magnetisation of a bar magnet is `5xx10^(4)A-m^(-1)`. The magnetic length and the area of cross section of the magnet are 12cm and `1cm^(-2)` respectivley. The magnitude of magnetic moment of this bar magnet (in SI unit) is.

Options

A. 0.6
B. 1.3
C. 1.24
D. 2.4

Answer

A

Explanation

We know that that , intensity of magnetisation , `l=(M)/(V)` ( where , M= magnetic moment , V=volume )
So, ` M=lV=5.0 xx 10^(4) xx (12)/(100) xx (1)/((100)^(2))`
`=60xx 10^(4) xx 10^(-6)=0.6A-m^(2)`