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Magnetic Field

Magnetic Field, B

To define Magnetic field, we start with the word field. Field means a region or space.
The magnetic field is defined as a region where the magnetic force can be felt. In other words, a force (repel/attract) can be felt in the region.
Bar Magnet

We will find that 2 North(N) poles will repel if we bring the poles of two bar magnets together.
Same goes to that of 2 South(S) poles. However North and South pole attracts.
The strength and direction of the field are represented by lines. Knowing that, the direction of magnetic field is from North to South.

Magnetic field is able to be detected by
1) Compass (have been used over 2000 years
2) Hall Probe

Applications:
Swipe cards, Video tapes & Computer discs -use magnetism to store information.

 History:

In 1819, Hans Christian Oersted noticed that a compass needle was deflected by an electric current in a nearby wire. Remember!! the compass is used to detect any existance of magnetic field. By this observation, he discovered that there is a link between electricity (electric current) and magnetism (magnetic field). An Electric Current , I is always surrounded by a Magnectic Field, B.
(i.e. long straight wire, coil & Solenoid in next entry)

Do you still remember the meaning of electric current?Let us recall: electric current is the movement of charged particles.

In 1864, James Clerk Maxwell, proved that all magnetic fields are caused by the movement of charged particles.

Hence, we can say that , apart from natural source of magnetic field that is the earth, we have 2 different ways of producing magnetic fields:
1) Permanent magnets (e.g. bar magnet)
2) Electric Currents.


Thank You,

Mdm Ummi Atiah
KMPk
~ May it Benefits You ➽💕

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