Poles of Magnets

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The ends of the magnet are known as the poles of the magnets. One side end is known as the North Pole and the other side of the magnet is known as the South Pole. If we take two magnets and one magnet's south side is kept within distance of the north side of another magnet, then both will get attached. This property is known as the property of attraction. And if we place the magnets in the same direction, then both will become apart from each other. This property of magnet is known as the property of repulsion. We can conclude from this that opposite poles attract each other while similar does repulsion.

Magnetic Field Lines

The influence of magnetic forces in a region is described by magnetic field lines. Itâ€™s a visual used to depict and understand magnetic field lines. At a regional positionÂ  they describe the direction of magnetic fields in monopoles.

Though monopoles do not exist in nature so we describe field lines using different methods. One of them is the close connection between both the monopoles of the magnets and electric charges. Few conventions which we have adopted regarding the field lines are: that the field lines enter from the South Pole and get out from the North Pole of the magnet.

In principle, every position at the space field lines can be calculated. But in the visual medium itâ€™s hard to represent. Therefore to indicate the field strength we use density of field lines.Â

Monopoles: theoretical objects which have either north or south poles are known as the monopoles. Another way to analyse these poles are by magnetic charges, analogous to protons and electrons. As their existence is disputed so they can be artificially synthesized. It should be noted that electrostatic phenomenon is reduced by monopoles. The field lines converge at the south pole and emerge out of north poles.

Properties of Magnetic Field Lines

Magnetic field lines depict the direction of magnetic force. Discussing some of the properties of magnetic field lines. Magnetic field lines always form closed loops. These field lines originate from the north pole and end at the south pole by convention. The direction inside the magnet inversely appears to move from south pole to north of a bar magnet. The field lines move or bulge out when itâ€™s moving from an area of higher permeability to an area of low permeability. Each of these lines contain the same strength. They never cross each other.

Direction of Magnetic Field LinesÂ

Magnetic field lines are the lines which show the direction of magnetic force.Â

In a bar magnet if there are two poles one designated as the north and the other as the south, the magnetic field lines make a loop and enter from the south and get outside from the north direction. In a monopole magnet the field line emerges from the north pole and converges in the south pole. If we isolate monopoles magnets in nature they will undergo similar interactions which are in an electric field. The electric field of charges and magnetic fields of monopoles will behave in a similar manner and a similar electric field would be observed in magnetic monopoles. The elegance of this ideaÂ  exists no matter whether poles exist or not.

Coulomb type law is seen when one claims the definition of magnetic chargeÂ  analogous to electric charge.

North and South Poles

A magnet consists of two poles of magnets which are designated as the south pole and the north pole. There are many magnets but primarily we will discuss the bar magnets. What we have observed above are the two poles of the magnets north and south poles. If we freely suspend a magnet it will always point out in the north direction. This property is known as the north pole of magnet.

Just opposite to the north lies the south end or south pole. If we see a compass which is itself a magnet and it always points in the north direction, except in the case of a strong magnet. In that case the pointing of the compass is different . The magnet field causes magnetic force which further causes attraction or repulsion.Â

On the earth's northern hemisphere the north magnetic pole is the wandering point at which earth's magnetic field points downwards.Â

This is the reason why the compass needle points in the north direction when freely suspended. But as we move towards the north magnetic pole it will point horizontally or in a straight direction.

According to the flux lobe elongation and magnetic flux the north magnetic poles move. Its counterpart south is in the south magnetic pole. The north and south poles are not antipodal as our earth is not symmetrical.

Q1. Why Does Metal Get Stuck to Poles of the Magnet?

Answer: When the north pole of the magnet is kept close to the south pole of the magnet it gets attracted towards the south pole. Whereas, when a north pole comes in contact with the north pole it pushes away, same is the case when itâ€™s brought near a metal.

Q2. Which is the Most Magnetic Material?

Answer: Mineral Magnetite is the most magnetic material found in nature and is also called lodestone. The domains which are magnetic of magnetite naturally align with the earth's axis.

Q3. What Causes Magnets to Attract or Repel?

Answer: A magnet attracts when kept in the opposite direction to another magnet and repels when kept in the opposite direction. Itâ€™s not the magnet that attracts or repels but it's the field lines force which repels each other from attraction or repulsion.

Q4. Magnets can Hold their Charges for How Long?

Answer: If we talk about the permanent magnet then it's kept and used in optimum working condition. This will keep its magnetism for many years.

Â For example a neodymium magnet loses its 5% of magnetism every 100 years.