What are the key characteristics of a magnetic field?
Magnetism is the property of how a material responds when subjected to a magnetic field. The magnetic field is a change in energy within a volume of space. The molecules in a magnet are aligned to all face one way, which gives the magnet its magnetic field. Sometimes the molecules can align permanently, making a permanent magnet, a permanent magnet is typically a ferromagnetic material, such as iron. Temporary magnets molecules only line up for a period before losing their magnetism. The length of the time they are aligned varies. If it’s suspended freely, a permanent, the magnet will rotate itself in a direction which matches the earth’s magnetic field. One way to see the magnetic field is to experiment with the bar magnet, iron filing, and a card.
Properties of magnetic field lines
- They always form closed loops.
- No two magnetic lines intersect.
- Outside they seem to travel from north to south and inside south to north.
- They leave the North Pole and enter the South Pole normally.
- It is a vector quantity.
- The magnetic field lines are crowded near the pole where the field is strong and far from the magnet where the field is weak.
- In case the field lines are parallel and equidistant, they represent a uniform magnetic field. The Earth’s’ magnetic field is uniform limited space.