Meaning of Magnets – Looking for a falling needle will take time by hand, of course it will take a long time, although we can guess where it falls, but it will be difficult for sure.
Try using a magnet. The trick is to bring the magnet close to the surface of the floor and the needle-like metal will be attracted to the magnet. The search process will be easier.
Ever noticed the nail scavengers on the street? They also used a stick with a magnet attached to the end so they just combed the road and attached all the metal including nails which would later be collected.
Why can magnets attract metals? Can all metals be drawn? Can we make magnets? Can magnetic properties be removed? Let’s talk more about the power of magnets
A. Meaning of Magnets
Initially, in a metal mining area, a metal was found that was able to attract other metals, although not all metals could be attracted. Then the metals that were found turned out to be strongly attracted, some weakly attracted and some unable to attract metal.
Magnet itself comes from the Greek word magnítis líthos which means Magnesian stone. The region has magnetic stone content, and Magnesia itself was a region in Greece in the past currently called Manisa.
If a magnet is between iron powder, then you will see a lot of powder sticking to both ends of the magnet. The more in the middle, the less iron powder sticks.
This means that the two ends of the magnet are where the attraction force is the strongest. While the middle part has no magnetic or neutral attraction.
B. Magnetic Properties
What distinguishes magnets from other things? Of course there is a unique property that the magnet has, what is it? Learn various interesting facts about magnets through the book Jago Fisika: Magnet Dan Listrik
1. magnets can attract certain things
Magnets only attract certain objects around them, so not all objects can be magnetized even if the objects are around them.
There are certain materials that can be attracted by magnets. The materials are metal type. But, not all metals can be magnetized, depending on the type. Then there are metals that are attracted so strongly, but there are also weak ones.
2. A magnet has two poles
Magnets have two poles, the positive pole and the negative pole. The two Poles are located at the end. That’s where the magnetic force is so strong.
Eits but don’t expect to find north and south writing. The north pole of the magnet will always face the north of the earth, and the south pole of the magnet will always face the south of the earth.
Hm.. why do magnetic poles always point north and south?
The answer is because of the influence of the Earth’s strong magnetic field.
The Earth’s magnetic field was discovered in 1600 by a William Gilbert, the most prominent scientist in England. Gilbert theorized that the Earth functions as a giant magnetic bar that affects all magnetic objects on Earth.
Quoted from NASA that, the Earth’s core is an electromagnetic solid surrounded by a liquid core (liquid iron and nickel) in which electric current flows.
The electric current in the molten core causes the Earth’s magnetic field to be so strong that it covers the entire Earth as well as the outer space around it.
Earth as a very large magnet with the north pole of the earth’s magnet around the south pole of the earth, on the other hand the south pole of the magnet around the north pole of the earth.
The north pole of the free magnetic field faces north because it is pulled by the south pole of the earth’s magnet which is located around the north pole of the earth. The south pole of the magnet is free to face south because it is pulled by the north pole of the earth’s magnet which is located around the south pole of the earth. The direction of the lines of magnetic force in the earth’s magnetic field is from the direction of the south pole of the earth to the north pole of the earth. How can you?
The location of the earth’s magnetic poles is not exactly the location of the earth’s poles! Therefore the compass needle will form an angle with the north-south current as well as with the horizontal plane of the earth. The direction of the magnetic axis of the compass needle forms an angle with the north-south direction of the earth. This angle is called the declination angle.
The declination angle is the deviation of the direction of the compass needle from the true north and south direction of the earth. The magnitude of the angle of declination in various places is not the same, and also changes every year.
In addition to the angle of declination, there is also the angle of inclination. The angle of inclination is the angle formed by the magnetic axis of the compass needle with the horizontal direction of the earth. It turns out that the magnetic axis of the compass needle forms an angle with the horizontal or horizontal line of the earth.
Well, the navigation of ships and airplanes uses a compass as a direction indicator. By observing the direction of the magnetic pole of the compass needle, it can be estimated which direction is north and south.
By reading the angle of declination on the compass, the actual north-south direction of the earth can be determined.
Because the angle of declination changes every year and as technology advances, sooner or later the compass is considered less accurate as a direction indicator.
It is Radio Beacons that replace the use of a compass to inform the north and south direction of the earth, including the wind angle accurately.
3. Different poles will attract each other, same poles will repel each other.
If the poles of the same type are brought together, there will be a force of repulsion, while if the poles are opposite, there will be an attraction.
Suppose we bring the north pole closer to the north, then the two magnets will repel each other. But if we bring the north and south poles closer together, there will be an attractive force.
If we use a natural magnet and when we bring the two ends together it turns out that they repel each other then we can conclude that their poles are different, while if they attract each other, be sure that the poles are different.
Oh, yes. If a magnet is cut into small pieces, it turns out that the small pieces will form new magnetic poles. No matter how small the size, it still has magnetism.
So a magnet consists of small magnets that are located in a row from the north pole facing the south pole of the magnet and on the other hand the south pole faces the north pole of the magnet. These small magnets are called elementary magnets.
4. Magnetic force can penetrate the barrier.
Magnets have a force that can penetrate objects. So even if there is metal blocked by glass or paper, the metal is still affected by the magnetic force. So it’s not magic, it’s not magic if the magnet can still attract metal even if it’s blocked.
To prove it, just sprinkle iron powder on paper and put a magnet behind the paper. Although blocked by paper, the iron powder will move as the magnet is moved. Want to be moved up, down to the right and to the left the iron powder will follow.
5. Has a magnetic field
A magnet has a magnetic field that will produce a magnetic force. The magnetic force of a magnet will get closer if it is near the magnetic field, but will move away if the distance is also away from the magnetic field
a. Definition of magnetic force field
What is a magnetic force field?
The magnetic force field is the space around the magnet that still has the influence of the magnetic attraction force.
The field of magnetic force is described as curved lines called lines of magnetic force.
Curious to see what the magnetic line style looks like? try to sprinkle iron powder on white paper, if we keep a magnet behind the paper, then the iron powder will show a regularity, they will be in the area around the magnetic field
b. Magnetic style line pattern
The pattern of style lines when poles of the same type are brought close together, the style lines formed move away from each other, until there seems to be an empty space. For example, we bring the north pole closer to the north pole or the south pole to the south pole.
Meanwhile, if poles of different types are brought closer, the north pole if brought closer to the south pole,
then a pattern of lines of force can be seen connecting each other from pole to pole.
C. Types of Magnets
1. Types of magnets based on their origin.
Where does the magnet actually come from? Based on its origin, magnets are divided into two, namely natural magnets and artificial magnets, which are discussed in the SMA/MA/SMK Kitab Keramat Listrik&Magnet: Seri Pendalaman.
a. Natural Magnets
This natural or created magnet was discovered by the people of Magnesia in the past. This magnet has magnetic properties since it was discovered. Usually natural magnets are in the form of rocks. Natural magnets also have special characteristics, which are permanent. That’s why the magnetism of natural magnets is harder to lose.
So, when this magnet was discovered, it already had the ability to attract things around it without human intervention or being formed naturally.
b. Artificial Magnets
Based on the need that is increasing over time, then make a magnet.
So along with the development of time, humans began to be able to make artificial magnets.
Not everything can be made into a magnet. Things that have elemental magnets can be made into magnets. As discussed earlier that the magnet consists of domains or elemental magnets
1). Artificial magnets based on the strength of the magnet
a) Permanent magnet
Based on their strength, artificial magnets are divided into permanent magnets. Artificial magnets have permanent magnetism if their domains or elemental magnets are in a fixed order. For example, in steel, the elemental domains or magnets are indeed difficult to arrange, but once magnetized it turns out to be regularly organized.
b) Temporary Magnet
Artificial magnets have temporary magnetism if the domains or elemental magnets can only be organized for a while and then soon become scattered or chaotic again, for example iron. It turns out that iron is an elemental magnet that is easy to set up, but unfortunately it will soon be scattered again. If it scatters back then the magnetic strength is gone.
2). Based on the material, artificial magnets are divided into 3 groups
Ferromagnetic is a material that if made into a magnet then the magnetism is very strong.
Examples of ferromagnetics are iron, steel, nickel, and cobalt. In addition to being strong as a magnetic material, these materials are also very strongly attracted to magnets.
Paramagnetic is a substance that, if made into a magnet, has weak magnetic properties, and cannot be made into a magnet. Examples of ferromagnetic materials are aluminum and platinum.
Diamagnetic is a material that cannot be made magnetic.
The reason is because there is no elemental magnet in the material.
3). How to make artificial Magnets
There are two ways to make magnets namely:
a). Making magnets by rubbing
Iron or steel rubbed with a magnet will become a magnet. How to rub iron or iron to become a magnet?
The way to make a magnet by rubbing is to rub iron or steel in the same direction. Directional movement is able to make elementary magnets become directional
b). Make a magnet with an electric current.
How to make a magnet with electric current is:
Wrap the copper wire around the nail, connect the end of the wire to the battery pole. Observe, Once connected, the nail will have a magnetic force and can attract metals around it.
Why is that? Electric current flows from the power source to the coil wire, the larger size nail made of iron is in the electric field. Small nails are attracted to big nails.
So as long as the big nail is in the electric field the big nail will become a magnet. If we cut the current, the big spike will become neutral again. Because magnets always have 2 poles, namely north and south, how do you determine which is the north and south poles? This way, the electric current will flow from the positive pole to the negative pole.
In the event according to the picture, it means electric current in the direction of clockwise rotation. As long as the electric current flows, the nail end B is the north pole and the end A is the south pole.
So when the electric current in the coil wire flows clockwise, the iron or steel end where the electric current enters the wire is the south pole while the place where the current leaves the coil becomes the north pole.
When the electric current in the coil is counter-clockwise, where the current enters the iron or steel end as the north pole and the other end is the south pole.
It turns out that the number of windings and the voltage given will affect the size of the magnet produced.
The greater the electrical voltage used, the greater the magnetic intensity, the greater the electric current, the greater the magnetic strength and the more turns of the coil, the stronger the magnetic intensity.
c). Making a magnet by induction
If we use a US magnet to induce iron AB until it becomes a magnet with A as the north pole and B as the south pole of the induction magnet. If we move the magnet US away then the iron aB becomes neutral and will not attract the metal anymore
D. Shapes of Magnets
Magnets found in a mine have an irregular shape. While the magnets that are made have a shape that is adapted to the needs. Magnets are currently a key component of modern technology as discussed in the book Electricity and Magnets.
Magnetic forms among them
1. Rod magnet
A rod magnet is a rod-shaped magnet or like a small block or cube.
These magnets are usually used for door locks on glass and wooden cabinets. In addition, it can also be used as a cover for other things, such as pencil boxes, gift boxes, etc
2. Horseshoe magnet
Horseshoe magnets are also known as horseshoe magnets. Why? Because its shape resembles a poultice that is used as a horse shoe.
The use of u magnet or horseshoe magnet is to lift magnetic objects
3. Magnet needle
Needle magnets have a flat, elongated, and pointed end. A needle magnet is usually used to make a compass work as a wind direction indicator.
4. Cylindrical magnets
Cylindrical magnets have a cylindrical shape, round and flat. The use of cylindrical magnets is largely similar to the use of bar magnets.
These magnets are used for door locks on glass and wooden cabinets.
Not only that, ino magnets can also be used to cover other things, such as pencil boxes, gift boxes, etc.
5. Ring magnet
Its name is also a ring magnet so the shape of a ring magnet resembles a ring. This magnet has a circular shape with a hole in the middle.
Ring magnets are used to make loudspeakers, such as speakers in radios, cinemas, or mobile phones. Ring magnets can also be used in electric motor machines.
E. How to Eliminate Magnetism
It turns out that magnetism can be removed. How to remove it is as follows:
- Flowed back and forth
That is the information about the meaning of magnet that should be known. It is certainly very useful for us in our daily lives, because many things around us use magnets in their operation. Also read the following other articles: