Question

 

Describe the different types of magnets that you can buy and use, as well as their properties.

Answer 1

The three types of magnets are

1. Temporary,
2. permanent and
3. Electromagnet

1. Temporary magnet

A temporary magnet is a magnet that remains magnetized for only a small time interval as compared to a permanent magnet. It is generally made of soft iron, that is usually easy to magnetize; however, temporary magnets lose most of their magnetic properties when the magnetizing cause is discontinued.

Uses of temporary magnets would be paper clips and nails and other soft iron items as examples used for temporary magnets. Temporary magnets are commonly used in electric motors and telephones and speakers. Temporary magnets are also used to make temporary electromagnets

2. Permanent Magnet

These types of magnets can retain their magnetism and magnetic properties for a longer time. Strongly magnetized hard materials make up permanent magnets. A perfect example of a permanent magnet is the Bar Magnet. This magnet widely explains the behavior of magnets. Actually, we call permanent magnets as Bar Magnets also.

A good permanent magnet should produce a high magnetic field with a low mass, and should be stable against the influences which would demagnetize it. The desirable properties of such magnets are typically stated in terms of the remanence and coercivity of the magnet materials.

Permanent magnets are used in hard drives, motors, cars, generators, televisions, phones, headphones, speakers, transducers, sensors etc. The most common use of a magnet is the pulling force to attract other magnetic items but it has various functions in electronic tools as well.

3. Electromagnet

An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire creates a magnetic field which is concentrated in the hole, denoting the centre of the coil.

The main properties of an Electromagnet are:

(i) An electromagnet is temporary in nature.

(ii) An electromagnet is made of a soft iron core. (iii) The magnetic field strength can be changed. (iv) An electromagnet can be easily demagnetized by switching off the current.