Suppose that the source of earth's magnetism is a magnetic dipole at the earth. Find the moment of this magnetic dipole if the strength of earth's magnetic field at the equator is `4xx10^(-5)` T . Given , radius of the earth `6.4xx10^(6)mand(mu_(0))/(4pi)=10^(-7)T.m.A^(-1)`.

Answer

3

Explanation

the strength of the earth's magnetic field at the equator `=4xx10^(-5)T`
Radius of the earth , `R=6.4xx10^(6)m`
`thereforeB=(mu_(0))/(4pi).(p_(m))/(R^(3))" "[p_(m)` the magnetic dipole of the earth ]
`" or, 4xx10^(-5)=10^(-7).(p_(m))/((6.4xx10^(6))^(3))`
or , `p_(m)=(4xx10^(-5)xx(6.4xx10^(6))^(3))/(10^(-7))=1.05xx10^(23)A.m^(2)`