Electromagnetic induction.
Electromagnetic induction is the phenomenon discovered by Faraday from England in 1831. Isn't a difficult impression received?
In short ...
Electromagnetic induction is a phenomenon in which change of a magnetic field causes the driving force which sends current to a circuit.
The experiment using a coil and a magnet
We conduct the easy experiment using a coil and a magnet, and explain electromagnetic induction.Experiment:
Connect a coil and a galvanometer.
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A bar magnet is moved.
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Signs that the needle of a galvanometer touches are investigated.
| N approaches a coil. ↓ A needle touches the left. |
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| S approaches a coil. ↓ A needle touches the right. |
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| N separates from a coil. ↓ A needle touches the right. |
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| S separates from a coil. ↓ A needle touches the left. |
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| does not move. ↓ Nothing changes. |
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From this experiment,
"If a magnet approaches, it will oppose.
If a magnet separates, it will pull. "
In order to make a coil generate a magnetic field, an induced current flows.
That is, it turns out that the coil is working to maintain the state of the magnetic field in a coil.
Such a phenomenon does not necessarily happen only with a coil.
This technology is used for familiar various things.
Michael Faraday (1791〜1867)
He discovered the law of electromagnetic induction, and diamagnetism and the law of electrolysis.
Although Faraday has not received high education, he is one of the scientists who affected history.
His distinguished services have led to development of electric technology closely.
About electromagnetic induction discovery
He found the phenomenon called electromagnetic rotation.
One day, he was reading the paper about an electromagnet.
He thought.
Is a magnet able to continue moving the circumference of current?
After that.
Equipment was made using mercury, wire, the magnet, Volta's battery, and the lead.
It is electromagnetic rotation.
This invention is related to discovery of electromagnetic induction.
【Reference】
http://www.tele.soumu.go.jp/kids/time2/time2.htm
http://ja.wikipedia.org/wiki/マイケル・ファラデー
