——Electromagnetic force——
There are several fundamental forces that hold our universe together.
One of these, of course, is gravity, the force between objects that have mass.
Another important force is the electro magneticforce.
The electromagnetic force is responsible for chemical reactions.
Without is, there would be no atoms or molecules.
Up until a couple of hundred years ago, very little was known about this force.
Learning about the electromagnetic force and how to use it was a major step forward.
It revolutionized communication, transportation and manufacturing.
Imagine what life would be like without electricity!
The electromagnetic force has two parts, the electric force and the magnetic force.
The electro force is the force between electrically charged particles, such as electrons and protons.
Electric charges attract or repel each other with a force that depends on the distance between them.
The magnetic force is the force between magnetic poles, such as the north and south pole.
Infact, the earth is like a large bar magnet, with a north and a south pole.
Many animals use the earth’s magnetic field to navigate during their migration.
We can also see this magnetic field when we use a compass.
Why does the earth have magnetic field?
Many scientists believe that the Earth magnetic field is due to the Earth’s rotation.
Deep inside the Earth is a solid iron core, surrounded by a liquid metal outer core.
The moving electric currents inside this liquid metal create a magnetic field.
The earth magnetic field is important because it protects us from the solar wind.
The solar wind is a current of charged particles coming at us from the sun.
When the solar wind nears the earth, the earth’s magnetic deflect it away.
This protests the Earth from the radiation, which can be dangerous to life.
It also protects the satellites that we use for communication.
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