Earth has a number of interesting properties and one such property is that earth acts like a magnet. Scientists have found that earth acts like giant magnet with a north magnetic pole and south magnetic pole acting like real life bar magnets. And this bar magnet property allows earth to be surrounded by a strong magnetic field which interacts with electrical charge and magnetized matter.
But what makes earth act like a bar magnet is an interesting question? So let’s check out the exact explanation.
According to scientists, the earth’s magnetic field originates from the outer core filled with liquid iron. The liquid outer core surrounds the solid inner iron core and transfers heat to the mantel and surface via convection. The magnetic field is generated by the ‘Dynamo Effect’ which is caused by the motion of the liquid part in the core. The movement of the liquid produces a current in the moving conductor adding to the existing current.
The motion of the liquid inside the core is because of convection process. The inner core of the earth is much hotter than the surface, so the hot fluid in the core rises towards the mantel. The rotation of the earth adds an extra force which generates a roughly stable pattern and continuously replenishes current to maintain the magnetic field. So, Earth never loses its magnetic field and acts as a bar magnet by the self-sustaining process.
Finally, Earth is the only planet to have a strong magnetic field as other planets have a weaker or negligible magnetic field. It is also witnessed that some moons in the solar system show the evidence of magnetic field may be in the past or present. So, heavenly body acting like a bar magnet is an interesting natural phenomenon.