Earth's magnetic field and the magnetic field of a bar magnet have similarities, such as having two magnetic poles and field lines. However, they differ in how they are generated and the strength of the field.
There are several ways in which Earth's magnetic field and the magnetic field of a bar magnet are similar:
Both Earth and a bar magnet have two magnetic poles, a north and a south pole.
Both magnetic fields have field lines that are closed loops that extend from the north pole to the south pole.
In both cases, a compass needle aligns itself with the magnetic field lines, indicating the direction of the magnetic field.
However, there are also differences between the two:
Earth's magnetic field is generated by the movement of molten iron in its core, while a bar magnet's magnetic field is generated by the alignment of its atoms.
The strength of Earth's magnetic field is much weaker compared to a bar magnet, as the magnetic field of a bar magnet rapidly decreases with distance from the magnet.