Types of Magnetic Material

Magnets are made of materials that attract objects made of certain substances like iron, cobalt, and nickel. The substances that are attracted by the magnet are called magnetic substances. For example, iron, steel, nickel and cobalt All types of materials and substances posses some kind of magnetic properties., but normally ferromagnetic materials are called magnetic materials. The materials can be classified into following categories based on the magnetic properties shown by them: The substances that are not attracted by the magnet are called non-magnetic substances. For example, wood, stone, leather, plastic,aluminium and copper.

1. Diamagnetic Materials:

These materials are barely magnetized when placed in a magnetic field. Magnetic dipoles in these substances tend to align in opposition to the applied field. In effect, they produce an internal magnetic field that opposes the applied field and the substance tends to repel the external field around it.

This opposing field disappears as soon as the external field is removed.

Ex: Gold, water, mercury and even animals!

2. Paramagnetic Materials:

In these materials the magnetic dipoles in the Magnetic Materials tend to align along the applied magnetic field and thus reinforcing the applied magnetic field. Such substances are attracted by a magnet if it applies a sufficiently strong field. It must be noted that such materials are still feeble magnetized and the magnetization disappears as soon as the external field is removed. Ex: Liquid oxygen, sodium, platinum, salts of iron and nickel.

3. Ferromagnetic Materials

We are most familiar with these materials as they exhibit the strongest magnetic behaviour. Magnetic dipoles in these materials are arranged into domains where the arrangements of individual magnetic dipoles are essentially perfect that can produce strong magnetic fields. Normally, these domains are usually randomly arranged and thus the magnetic field of each domain is cancelled by another and the entire material does not show any magnetic behaviour.

However when an external field is applied, the domains reorient themselves to reinforce the external field and produce a strong internal magnetic field that is along the external field. Upon, removal of the external field, most of the domains stay put and continues to be aligned in the direction of the (erstwhile) magnetic field. Thus, the magnetic field of the Magnetic Materials persists even when the external field disappears. This property is used to produce permanent magnets that we use every day. Iron, cobalt, nickel, neodymium and their alloys are usually highly ferromagnetic and are used to make permanent magnets.

Sample Questions

(More Questions for each concept available in Login)

Question : 1

Magnets are made of materials that attract objects made of certain substances like _______________________.
A. Iron	B. Nickel	C. Cobalt	D. All of these
Right Option : D
View Explanation

Question : 2

Which of the following are correct : (a) The substances that are not attracted by the magnet are called magnetic substances. (b) Diamagnetic Materials are barely magnetized when placed in a magnetic field.
A. Only (a) is correct.		B. Only (b) is correct.
C. Both (a) and (b) are correct.		D. None of these.
Right Option : B
View Explanation

Question : 3

Magnetite is a _______________________
A. A naturally occuring mineral	B. An artificial magnetc	C. Both the above	D. None of these
Right Option : A
View Explanation