Man-Made Magnets
Document Actions
Magnets have a magnetic field that exists around them. The magnetic field strength is very strong right next to the magnet and gets weaker further away from the magnet. The effect of a magnetic field can be seen by placing small iron filings around a magnet as shown below. The filings line up with the magnetic field. Magnetic fields are weaker in air and stronger when it can exist in a ferrous material like iron. This is because iron allows the magnetic field to pass through it more easily than air does. The magnetic field strength will increase when it can exist in iron and decrease when it has to exist in air or some other non-ferrous material. If you want a magnet to stay strong while it is stored, stick it to a piece of iron while in storage.
The magnetic field has a direction of flow that leaves the North Pole and enters the South Pole. This is why when two magnet's north poles are brought close together, they repel each other. When a north pole and a south pole are brought close together, they are attracted to each other.
Remember:
- Like poles repel each other. North-North, South-South.
- Unlike poles attract each other. North-South, South-North.
