Magnetism - magnetic fields;
Of course. Here is a comprehensive explanation of magnetism and magnetic fields, broken down from the fundamental concepts to their real-world applications.
1. What is Magnetism?
At its core, magnetism is one of the fundamental forces of nature. It’s the force exerted by magnets when they attract or repel each other. This force is carried by an invisible area of influence called a magnetic field.
The key takeaway is that magnetism is caused by moving electric charges.
2. The Fundamentals of Magnetism
a) Magnetic Poles
Every magnet has two poles: a north pole and a south pole. This is similar to how electric charges come in positive and negative, but with a crucial difference.
- Opposites Attract: The north pole of one magnet will attract the south pole of another.
- Likes Repel: The north pole of one magnet will repel the north pole of another (and south will repel south).
This is why a compass needle (which is a tiny magnet) aligns itself with the Earth’s magnetic field, with its north pole pointing towards the Earth’s geographic North Pole (which is actually a magnetic south pole!).
b) No Magnetic Monopoles
This is a critical rule in magnetism. If you take a bar magnet and cut it in half, you don’t get a separate north pole and a south pole. Instead, you get two smaller magnets, each with its own north and south pole. This can be repeated down to the atomic level. As far as we know, isolated north or south poles (called “magnetic monopoles”) do not exist in nature.