what is Magnetism?

Question

i need the concept of Magnetism more than the equations
Electromagnetism too ..

Answer 1

The ancient Greeks, originally those near the city of Magnesia, and also the early Chinese knew about strange and rare stones (possibly chunks of iron ore struck by lightning) with the power to attract iron. A steel needle stroked with such a "lodestone" became "magnetic" as well, and around 1000 the Chinese found that such a needle, when freely suspended, pointed north-south.
The magnetic compass soon spread to Europe. Columbus used it when he crossed the Atlantic ocean, noting not only that the needle deviated slightly from exact north (as indicated by the stars) but also that the deviation changed during the voyage. Around 1600 William Gilbert, physician to Queen Elizabeth I of England, proposed an explanation: the Earth itself was a giant magnet, with its magnetic poles some distance away from its geographic ones (i.e. near the points defining the axis around which the Earth turns).




On Earth one needs a sensitive needle to detect magnetic forces, and out in space they are usually much, much weaker. But beyond the dense atmosphere, such forces have a much bigger role, and a region exists around the Earth where they dominate the environment, a region known as the Earth's magnetosphere. That region contains a mix of electrically charged particles, and electric and magnetic phenomena rather than gravity determine its structure. We call it the Earth's magnetosphere

Only a few of the phenomena observed on the ground come from the magnetosphere: fluctuations of the magnetic field known as magnetic storms and substorms, and the polar aurora or "northern lights," appearing in the night skies of places like Alaska and Norway. Satellites in space, however, sense much more: radiation belts, magnetic structures, fast streaming particles and processes which energize them.

Answer 2

The simplest way to understand magnetism is that when electrical charges move, they exert a force on other electrical charges that are in motion. Why do they exert a force on other moving charges? That is just the way nature and our laws of physics operate.

Now, you may ask: why do some materials appear to be magnetic and others do not? The reason is there are lots of electrons (moving charges) in any material - but they tend to move in random directions, so the forces caused by the motion of these billions and billions of electrons cancel out.

However, some substances (such as iron) have an atomic and crystalline structure so that not all the magnetic forces cancel out. If the spin and motion of these electrons are aligned, the substance will exert a magnetic force on other substances (such as other iron atoms) where the electron motion does not cancel out.

Electromagnetism is produced by causing a current (moving electrons through a wire). If wire is wrapped so that the electrons move in the same direction (such as all move clockwise) so their magnetic effect will not cancel out, they will also exert a force on other moving electrons in atoms such as iron where the motion of the electrons does not cancel out.

Answer 3

Magnetism, an aspect of electromagnetism, one of the fundamental forces of nature. Magnetic forces are produced by the motion of charged particles such as electrons, indicating the close relationship between electricity and magnetism. The unifying frame for these two forces is called electromagnetic theory (see Electromagnetic Radiation). The most familiar evidence of magnetism is the attractive or repulsive force observed to act between magnetic materials such as iron. More subtle effects of magnetism, however, are found in all matter. In recent times these effects have provided important clues to the atomic structure of matter.

Answer 4

Magnetism is the force of attraction or repulsion between various substances, especially those made of iron and certain other metals; ultimately it is due to the motion of electric charges.

Electromagnetism is a special form of magnetism. It is magnetism produced by the flow of electrons (electricity) through a wire.

Answer 5

A stable magnet is a mass (usually) of iron, nickel, or cobalt. These are the three original elements that have a natural magnetic tendency. In these modern times there is "nicad" (nickel-cadmium) and other mixtures of minerals to intensify a stable magnet. This is a dicipline to itself and becomes very technical in finding particular molecular combinations.

Once the stable magnet has been formed, if it is left alone, the magnet is still of use fifty years later. It requires no energy to maintain its field.

The field itself is formed by a multiplicity of small magnetic domains all aligning themselves in a single, particular direction. When this is done, an increase in magnetic line density appears in the space about the magnet. This increase in density is similiar to you turning up the volume in your radio. The sound is stronger and more energetic about the speaker than when it is turned down.

A stable magnet and an electromagnet each are the product of electrons. In the stable magnet the electrons have their frequencies lined in a particular direction, and that direction does not change. In the electromagnetic mass, that which forms the magnetic field is the passage of electrons along a wire surrounding a mass it is wound around.

When an electron is formed, it is formed of electromagnetic energy. It is for this reason that electrons do not wear down, become weaker in their value, or vanish after thousands of years of doing the same thing all the time. An electron appears when a very high frequency photon enters near the nucleus of an atom. An electron pair forms. The positive one is immediately annhilated because it is an "anti-matter" particle. The negative one remains. This is our everyday electron, and the one we will now consider as causing electromagnetic energy.

When an electron passes along down a wire it forms magnetic lines all along the outside the insulation of the wire. The wire with the electron (in reality it take a vast number of them to form an electromagnetic field) moving along it may be thought to be similar to an expansive "soaker" hose, with water extending out all along its length, but the water in this example is frozen in place so it doesn't disappear. The water extending outward is like that of magnetic lines extending outside a wire.

When the wire is wound around a iron core, in multiple layers, all the "pressure" from the magnetic lines passes into the iron that is willing to accept them, and this causes the atoms to align according the the pressure exerted on them. The same as were a soaker hose to be wrapped around a permiable substance. The greater the water density, the greater the force it would exert.

The negative and positive poles in an electomagnetic form as they do because of the necessity of the magnetic force to balance. If it did not instantly balance, there would be a great amount of heat energy to form within the mass. This is seen in an electric motor when the shaft is unable to rotate. If there is no heat sensor in the motor to shut the current off, the windings will begin to smoke.

To illustrate how the magnetic field of earth forms, by reason of a formed electric field, consider the following:

Due to the spin of our planet, there are forces extending from either pole of our planet to the equator. These two fields of force are known as the Coriolis Effect. This condition causes water to go down drains in opposite directions in the northern and southern hemispheres. What it also does, when these forces meet at the plane of our planet's equator, is that it forces the plasma within our planet to experience a strong shearing action. This shearing action within a plasma generates a vast electrical field that forms through our planet's equatorial region.

As when an electon passes down a wire generating a strong electrical field, which in turn forms a magnetic one, so ,also, in our planet magnetic fields are instantly formed at a right angle to the electric one - the plane of our equator. It is for this reason we have extending magnetic lines forming the north and south poles.

Answer 6

*attraction for iron;associated with electric currents as well as magnets;characterized by field of force.
*In physics, magnetism is a phenomenon by which material exert an attractive or repulsive force on other material.
*the forse of attraction between an object and a magnet,which pulls the object toward the magnet.
*The branch of physics that studies the properties of magnets and magnetic fields.
*Universal energy that gathers all,coming especially from the physical body.

I THINK U UNDERSTOOD THAT
THANK U!

Answer 7

the principle attrction of any two objects is called magnetism and the material is called magnet.

a new fact says that even two oppositely placed ships undergo magnetism property.

Answer 8

Electromagnetism? Well it creates all the magnetic fields we see in space, makes our planet orbit the Sun, and causes galaxies to spin so fast they flatten out into disk, but it also holds them together. This is why ridiculous theories like black holes need to be revised.

http://i43.photobucket.com/albums/e397/Bigpappadiaz/magcur.gif

Everything is electrified.

Answer 9

basically i'll say its the attractive & repulsive force in nature, owing basically to electric charges' movement...