Bar Magnet - Uses, Pole Strength, Definition, Types, Properties, Classification,

The properties of a bar magnet have always fascinated us since we were children. When orientated in a specific way, it attracts small particles of iron scraps and nails while repelling another magnet. We will study about bar magnets in particular, their properties, and other related issues in depth in this brief post.

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This Story also Contains

1. Classification Of Magnets:
2. What Is Bar Magnet?
3. Types Of Bar Magnets:
4. Properties Of Bar Magnet:
5. Magnetic Field Lines Of A Bar Magnet
6. Use of bar magnet:

Classification Of Magnets:

Natural and manmade magnets are divided into two groups based on how they acquired their Magnetism , how long they retain their magnetic abilities, and their magnetic field. Natural magnets are far weaker than manmade magnets and can be found in nature.

1. Natural magnets - Natural magnets have a weak magnetic field and are found in nature. Natural magnets are commonly found in lodestones.
2. Artificial magnets — Artificial magnets have a stronger magnetic field and can be manufactured by man-made techniques. They can also be shaped to fit your needs. A bar magnet is an artificial magnet that has been formed into a bar shape.

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What Is Bar Magnet?

A bar magnet is a rectangular section of an object that has permanent magnetic qualities and is made of iron, steel, etc. Ferromagnetic substance which has two poles, one north as well as one south, when suspended freely, magnet aligns so that northern pole faces earth's magnetic north pole due to Earth magnetic field. A freely suspended bar magnet rest in north-south direction. The magnetic lines of force inside a bar magnet are from south pole to north pole of magnet. Magnetism at the centre of a bar magnet is Zero.

Types Of Bar Magnets:

A bar magnet can be one of two types:

1. A cylindrical rod, commonly known as a rod magnet, has a thickness equal to or more than the diameter, allowing it to have a high magnetism property. These bar magnets are used in instructional, experimental, and research applications.
2. Rectangular bar magnets are used in the manufacturing and engineering industries because they have a higher magnetic strength and field than other magnets.

Related Topics Link,

• Magnetic Moment
• Magnetic Dipole Moment
• Magnetic Susceptibility

Properties Of Bar Magnet:

A permanent magnet's qualities are comparable to those of a bar magnet magnetic field.

1. At both ends, it has a north pole and a south pole. Even if you split a bar magnet in half, both portions will have a north pole and a south pole, regardless of how many pieces you break it into.
2. It has the strongest magnetic force at the pole.
3. If a thread is used to suspend this magnet in the air, it will not come to rest until the poles are oriented north south. This attribute is used by a Mariner's Compass to determine direction.

4. When two bar magnets are positioned near together, their unlike poles attract each other while their like poles repel each other.

Pole strength:

The ability of a magnetic pole to draw magnetic materials towards itself is known as magnetic pole strength.

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Magnetic Field Lines Of A Bar Magnet

Let's do the following task to help us grasp the notion of magnetic field lines. Let's put some iron filings on a piece of paper and sandwich a bar magnet between them. When we tap the paper, the fillings organize themselves in the manner illustrated in the diagram below.

The magnetic field lines that encircle this bar magnet may be seen in the patterns of the filings.

Magnetic field lines are imaginary lines that can be drawn along any magnetic substance's. Magnetic field lines have unique characteristics. number of magnetic field line passing through a closed surface is know as magnetic Flux

1. A magnet's magnetic field lines create continuous closed loops.
2. The direction of the net magnetic field B at any place is represented by the tangent to the field line.
3. The magnitude of the magnetic field B is proportional to the number of field lines crossing per unit area.
4. The lines of magnetic field do not cross.

How electromagnets are different from bar magnets?

Although electromagnets and bar magnets have comparable magnetic fields, they differ in the following ways:

1. Most bar magnets are blocks of ferromagnetic materials, whereas electromagnets are coils of wire surrounded by a ferromagnetic core. When an electric current is passed through electromagnets, they behave like bar magnets.
2. Electromagnets rely on external sources of electric current to generate their magnetic field, whereas bar magnets generate their own magnetic field.
3. Electromagnets do not have a consistent magnetic pull since they are regulated by an external source of electric current, whereas bar magnets do because they are permanent magnets.
4. The magnetic force of a bar magnet is constant and is determined by the material it is constructed of, whereas the magnetic force of an electromagnet may be changed by changing the quantity of energy flowing through the coil.

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Use of bar magnet:

1. In the laboratory, bar magnets are employed as stirrers for magnetic studies.
2. They can also be used in medical operations.
3. Magnets are used in electronic devices such as telephones, radios, and television sets.
4. Bar magnets are used in a variety of industries for collecting loose metals and preserving the magnetism of other magnets.

Alnico and neodymium bar magnet:

A discussion on bar magnets would be incomplete without mentioning Alnico and Neodymium bar magnets. Aluminium, nickel, cobalt, and iron are the main ingredients in Alnico magnets. These magnets produce a high magnetic field and maintain that field even when exposed to intense heat. Magnets consisting of neodymium, boron, and iron are known as neodymium bar magnets. Both magnets are tremendously powerful, but they are also extremely fragile.

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