Give information about Earth's magnetism.

(N/A) The strength of the Earth's magnetic field varies from place to place on the Earth's surface. The value of the magnetic field is of the order of $10^{-5} \,T$.
It was previously believed that the magnetic field arose from a giant bar magnet placed along the axis of rotation of the Earth deep in the interior, but this is not the truth.
The magnetic field is now thought to arise due to electric currents produced by the convective motion of metallic fluids (consisting mostly of molten iron and nickel) in the outer core of the Earth. This is known as the dynamo effect.
Earth's magnetic field lines are similar to the magnetic field lines of a bar magnet.
The axis of the dipole does not coincide with the axis of rotation of the Earth but is presently tilted by $11.3^{\circ}$.
The magnetic poles are located where the magnetic field lines due to the dipole enter or leave the Earth.
The location of the north magnetic pole is at a latitude of $79.74^{\circ} N$ and a longitude of $71.8^{\circ} W$, a place somewhere in northern Canada. The magnetic south pole is at $79.74^{\circ} S, 108.22^{\circ} E$ in Antarctica.
The pole near the geographic north pole of the Earth is called the north magnetic pole. Likewise, the pole near the geographic south pole is called the south magnetic pole.
There is some confusion in the nomenclature of the poles. As shown in the figure, for the magnetic field lines of the Earth, one sees that, unlike in the case of a bar magnet:
$(1)$ The field lines go into the Earth at the north magnetic pole $N_{m}$ and
$(2)$ Come out from the south magnetic pole $S_{m}$.