Electromagnetism Electromagnetism is the force responsible for both
Electromagnetism
Electromagnetism is the force responsible for both electricity and magnetism. If fact, you’ll see soon that there is no difference between the two! Oersted – (Denmark, 1820) While experimenting with electricity he noticed that a compass needle changed direction when it was placed near a wire with Electric Current running through it. He discovered a link between electricity and magnetism for the first time! But how exactly are the two connected? ?
Both electricity and magnetism are generated by moving electrons. When electrons (charged particles) particles move through a wire they are said to “flow”. They create what is called an electric current Electric current – The flow or movement of charge through a material. : cts So m a F e - Measured in Amperes (amps) - Flows in one direction - Creates a magnetic field
As current flows through a wire, a magnetic field is created around the wire. The field exists like an invisible “cylinder” around the whole length of the wire
The Bottom Line: Whenever electricity flows, you get magnetism. Whenever magnetism flows, you get electricity. In normal situations, this principle is sometimes hard to notice with your natural senses. There are, however some useful techniques that help us learn more about this relationship…. .
We can detect the presence of a magnetic field around a “live” wire using iron filings – just like we do with magnets. This gives us an idea of where the field is and it’s basic shape. For more detailed information, we can use another method……
When the direction of current flowing through a wire reverses, the effect can easily be seen using magnetic compasses. That’s because when the direction of current changes, so does the polarity of the magnetic field. The “right hand thumb” thumb rule is used to remember how current direction relates to magnetic fields.
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