Temporary magnet and permanent magnit?

A temporary magnet is a magnet that only retains its magnetism for a short period of time when it is in the presence of a magnetic field. Once the magnetic field is removed, the temporary magnet loses its magnetism. An example of a temporary magnet is an electromagnet, which is created by passing an electric current through a coil of wire.

A permanent magnet, on the other hand, is a magnet that retains its magnetism even when it is not in the presence of a magnetic field. These magnets are made from materials such as iron, nickel, and cobalt, and they have their own magnetic field that does not require an external source to maintain. Examples of permanent magnets include refrigerator magnets and magnets used in speakers.

Temporary Magnet

- Exhibits magnetic properties only when subjected to an external magnetic field.
- Induced by a temporary external magnetic field.
- Loses its magnetism when the external field is removed.
- Examples: Electromagnets, iron pieces in an MRI machine.

Permanent Magnet

- Retains its magnetic properties indefinitely without the need for an external magnetic field.
- Naturally occurring or created through specific manufacturing processes.
- Cannot be easily demagnetized (but can be done by strong opposing fields or high temperatures).
- Examples: Neodymium magnets, magnetite (lodestone), ceramic magnets.

Key Differences:

| Feature | Temporary Magnet | Permanent Magnet |
|---|---|---|
| Magnetic Field | Induced by external field | Inherent property |
| Magnetism | Temporary | Permanent |
| Demagnetization | Easy to demagnetize | Difficult to demagnetize |
| Examples | Electromagnets, iron in MRI | Neodymium magnets, lodestones, ceramic magnets |
| Applications | Devices requiring temporary magnetism, MRI machines | Motors, electronics, compasses |