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Topic: Magnet - Does northpole attracts electrons?  (Read 4185 times)

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Offline alawsareps

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Magnet - Does northpole attracts electrons?
« on: September 24, 2016, 12:57:28 AM »
I'm having hard time understanding how magnet works...

I just want to know why magnet is used to generate electric energy (electric generator), does the magnet's northpole attracts electrons and its southpole repels the electrons?


Offline Arkcon

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Re: Magnet - Does northpole attracts electrons?
« Reply #2 on: September 24, 2016, 07:47:05 AM »
Re: Magnet - Does northpole attracts electrons?

No.  Magnets don't work that way.  Not even remotely.  That isn't even a High School Chemistry level explanation.  That's a pre-secondardy school explanation.   That's a "Is the sky blue 'cause God painted an upside-down bowl" explanation.  I'm sorry to be so critical, I truly am.  But I'm worried this will become a long thread, of bad explanations like that.  One of our forum rules is you must write a good title, and we qualify that that the title can't be "Just Help."  But its also unfair to our group to have a title that has no bearing on the question.  You've done this before, in your other thread, http://www.chemicalforums.com/index.php?topic=87809.msg316382#msg316382, your  title is metallic bonding, your question is compound bonding.  If we answer either one, we've got it wrong.  And you get to say -- "Nevermind, I got it better elsewhere http://www.chemicalforums.com/index.php?topic=87809.msg316388#msg316388"  Please stop doing that.

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I'm having hard time understanding how magnet works...

Its a difficult physics puzzler, that is true.  I don't understand everything about the topic. 

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I just want to know why magnet is used to generate electric energy (electric generator), does the magnet's northpole attracts electrons and its southpole repels the electrons?

No.  As I understand it, cutting the magnetic field with a conductor induces a current within the conductor.  Its field crossing, not electron attracting.  That is what Faraday, and Pierre Curie determined, two millennia ago.  See if AWK:'s links help you understand.  You can post what you've learned, I'd like a good explanation for myself.
« Last Edit: January 11, 2017, 09:13:11 PM by Arkcon »
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline mjc123

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Re: Magnet - Does northpole attracts electrons?
« Reply #3 on: September 24, 2016, 06:11:40 PM »
Two centuries ago?

Offline Arkcon

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Re: Magnet - Does northpole attracts electrons?
« Reply #4 on: September 25, 2016, 08:04:26 AM »
Two centuries ago?

Heh.  I often make the joke, "In the last millennium.  No not that crap one we just finished, the other last millennium"  Or "The turn of the century, you know, the one that brought us the steam engine, the light bulb, generators, not the century that brought us the Kardashians."

Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline Enthalpy

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Re: Magnet - Does northpole attracts electrons?
« Reply #5 on: September 27, 2016, 07:42:37 PM »
I'm having hard time understanding how magnet works...
Be reassured: it's less than trivial for about everybody. But theories about what effects a magnet has are well established, and some people get decently easy with. There are always tricky cases, though.

[When a magnet in a generator produces electricity], does the magnet's northpole attract electrons and its southpole repel the electrons?

No. Without a relative movement, there is no force between a magnet and an electron. At least if neglecting the electron's magnetic moment, which is perfectly legitimate in electric machines.

But with a relative movement, yes. A moving magnetic field is equivalent to a static one plus an electric field, and it does apply a force on electrons. So a generator comprises permanent magnets or electromagnets, and it has conductors to scoop the produced current, and turning the shaft of a rotating generator moves the magnets relative to the conductors.

More numerically, a relative speed v an an induction B (both are 3D vectors, with a strength and a direction) create an electric field E=vΛB, where Λ is a vector product: E is perpendicular to both v and B, with a strength equal to the product of their absolute values times the cosine of the angle between v and B. That is, v and B must be perpendicular to achieve the biggest E. Look at a generator: v, B and the conductors are engineered pretty much perpendicular to an other.

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