Electricity and magnetism both play big roles in our daily life they are essentially two aspects of the same thing. The Earth’s magnetic field is shaped like the magnetic field of a giant magnetic field of a gigantic bar magnet and it has two poles, the magnetic north pole and the magnetic south pole. When a magnet is suspended or hold in such a way that is free to move, it always align itself in the north-south direction.
Magnetic field is a region in space where the magnet affects another magnet, such as the magnetic compass. Magnetic field occur whenever charge is in motion. As more charge is put in more motion, the strength of a magnetic field increases. At any point around the magnet, the field has a magnitude which depends on the magnetic flux per unit area. The direction is shown by the North pole of the compass needle. And the magnetic field is a vector quantity, and it is represented by B.
HANS CHRISTIAN OERSTED
In the year 1820 Oersted discovered that a magnetic needle aligns itself perpendicularly to a current-carrying wire, definite experimental evidence of the relationship between electricity and magnetism. While preparing for a lecture in his laboratory, Oersted unintentionally placed a magnetic compass under a current carrying wire. To his surprise, the magnetic needle deflected as if it were in the vicinity of a permanent magnet. This is the principle behind electromagnets.
In our recent activity, we observed that the compass-needle has been deflected from its usual N-S position this is due to the current-carrying wire. When we are performing the activity, it was really hard for us to figure out what we’re going to do and we really don’t have an idea on what and how we are going to do it but Sir Lex provide us an Advanced Electromagnetism Kit for us to use, it consists of all necessary materials that are to be used in building the set-ups we’re making. We can also saw clearly that the lines of magnetic force circle around the wire is in counterclockwise direction. With the use of some materials that were also provided to us such as; the copper wire, the rectangular wooden block, a 9V battery and of course a magnetic compass, we’re able to make our set-up that is like the discovery of Oerstred.
Michael Faraday
Michael Faraday contributed greatly to the understanding of electromagnetism. His discovery is the reverse of Oersted’s. He demonstrated that a changing current in a coil induces current in a nearby coil even if the coils are not physically connected. This is called the principle of electromagnetic induction.
With this principle, Faraday built the world’s first electric generator. In 1831 people were producing dynamos or generators, but somebody had to show them how to use electricity in communicating.
Michael Farday himself noticed that whenever a current-carrying conductor is in a magnetic field, it tended to move in a direction at right angles to both the direction of I and B.
A coil of wire in a magnetic field rotates continuously as long as it carries current. It is also noticeable what Faraday has been pointing out on his experiment through the changing magnetic field, which induces current in the coil of copper wire. The set-up we did to understand further this concept was a success because there is a deflection of the needle of the voltmeter, which indicated that there was current in it. Thus, a current-carrying coil shows magnetic properties. We refer to it as electromagnet which loses its magnetic property when there is no current in the wire. Unlike a permanent magnet, the strength of an electromagnet can easily be change by changing the amount of the electric current that flows through it. The materials used in this set-up are as follows: Voltmeter, Bar Magnet, Alligator clips and the coil of copper wire.
In conclusion, Oersted and Faraday’s discovery gave us great help in understanding the relationship between electricity and magnet or we also called electromagnetism it also had a great impact on today’s daily life.
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