Magnet - Definition, Types, Properties, Applications, FAQs

What is magnet/What is Magnetism/Define Magnet

A magnet is a material or thing that produces a magnetic field. This invisible magnetic field is responsible for a magnet's most notable property: a force that attracts or repels other ferromagnetic materials including iron, steel, nickel, cobalt, and others.
In other words, a magnet is any material that can attract iron and produce a magnetic field outside of itself. All known elements and numerous compounds had been investigated for magnetism by the end of the nineteenth century, and all had been determined to have some magnetic property. Diamagnetism, which refers to materials that exhibit a mild repulsion by both poles of a magnet, was the most prevalent property. When placed near a magnet, some materials, such as chromium, demonstrated paramagnetism, or the ability to induce weak magnetization. When the magnet is withdrawn, the magnetism fades. Iron, nickel, and cobalt are the only three elements with ferromagnetic characteristics.

List of Magnet Properties of magnet:

We already know that magnets are constructed of magnetic material. Magnets have a number of unique characteristics. They are as follows:

1. Magnets are attracted to ferromagnetic materials such as iron, cobalt, and nickel.
2. Magnetic poles with similar magnetic poles repel one other, while magnetic poles with opposite magnetic poles attract each other.
3. The directive property of a freely hanging magnet is that it always points north-south.
4. When the distance between the two magnets is smaller, the magnetic force between them is larger.

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Magnets of Various Types

The following are the three different types of magnets:

• Permanent magnet.
• Temporary magnet.
• Electro magnets.

Permanent magnet:-

The most commonly used magnets are permanent magnets. They're termed permanent magnets because they don't lose their magnetic qualities once they've been magnetised.

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The permanent magnets can be demagnetize as follows:

Magnets are subjected to severe temperatures.

When a magnet is pounded, the magnetic attraction between its atoms weakens.

The magnetic strength of one magnet will be reduced if it is struck with the other in an ineffective manner.

Permanent magnets are divided into four categories:

• Ceramic or ferrite
• Alnico
• Samarium Cobalt (SmCo)
• Neodymium Iron Boron (NIB)

Temporary Magnet:-

In the presence of a magnetic field, temporary magnets can be magnetised. These materials lose their magnetic properties of magnet when the magnetic field is removed. The commonly used temporary magnets include things like iron nails and paper clips.

Electro magnet:-

Electromagnets are formed out of a coil of wire that is coiled around a metal core made of iron. When this material is exposed to an electric current, it generates a magnetic field, which causes it to behave like a magnet. Controlling the electric current can change the strength of the magnetic field.

Magnets and Their Applications

Magnets can be used in the following ways:

• Magnetic needles and mariner's compass are both made of magnets.
• Generators, electric accelerators, and electric motors all use permanent magnets.
• Speakers, electric bells, and electric cranes all use electromagnets.
• Separating iron filling from other solid mixtures is done with magnets.

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How are magnets made?

The north-seeking poles of the atoms align in the same direction when you rub a piece of iron against a magnet. The force generated by the aligned atoms produces a magnetic field. The iron has transformed into a powerful magnet.

Some materials can be magnetised by an electric current. When electricity travels through a coil of wire, it creates a magnetic field. The field around the coil, on the other hand, dissipates when the electric current is turned off.

Poles of the Earth's Magnetism

The Earth has a magnetic field. Scientists aren't sure why, but they believe electric currents are generated by the movement of molten metal in the Earth's outer core. The currents form a magnetic field between the Earth's magnetic poles, with invisible lines of force flowing between them.

The North and South Poles are not the same as the geomagnetic poles. Due to activity well beneath the Earth's surface, the magnetic poles of the planet frequently shift. When molten material called magma wells up through the Earth's crust and streams out as lava, the shifting locations of the geomagnetic poles are recorded in rocks. The Earth's magnetic field magnetises strongly magnetic particles within lava as it cools and solidifies into rock. The particles align themselves along the Earth's force lines. As a result, rocks preserve a record of the geomagnetic poles' position at the time.

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