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Simple Question about Electricity

  1. Nov 30, 2015 #1
    Hey guys :) new here, Just a simple question to get started. looks like a great forum :D

    Is the following statement correct or incorrect?

    If I hold a normal magnet with north and south poles, and I move my hand in one direction parallel to copper wiring, will it generate an electrical charge that is "technically" usable, albeit it would be too weak for practical purposes?

    Thanks for the info! I know there's probably a lot of "well" and "but" about this, I just mean on the basic practical level, would that generate "electrical current" ?

  2. jcsd
  3. Nov 30, 2015 #2


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    Gold Member

    Move your hand perpendicular to the wire. The magnetic field needs to move across the wire.

    See 2:58 in this video
  4. Dec 1, 2015 #3
    thank you very much :)
  5. Dec 1, 2015 #4
    OK further question, correct me if i'm wrong but do try to forgive some smaller incorrect technicalities:

    A Bycicle powered electrical generator. Pedaling turns the belt which is basically making magnets inside the motor go 'round and 'round, generating electrical current in the surrounding copper wire at a fast enough rpm that it can be used for small things, Correct?
  6. Dec 2, 2015 #5


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    Gold Member

    Generally the rotor has the wires and the magnets are fixed.
    You can google this stuff easily. If you search for answers, and don't understand them, please feel free to ask questions. But at least expend a little effort first.

    "How does a bicycle generator work" only gets about 190,000 results in 0.3seconds.
  7. Dec 2, 2015 #6
    hmhm, Yes I have googled aplenty, and came to that conclusion. It just seems so simple that I feel I'm missing something. I have a particular idea in mind and i'm trying to learn enough to be able to build a basic model and see if it works. It would be an electricity generator, dare I say it, for "free" :D not free but free of the grid and completely DIY.
    Every vid i've seen that gets close people are always nay-saying and spouting off fancy theories. So I wanted to see here if people jumped on it as being impossible or if basically, thats how to produce electricity.

    I'll do some reading and maybe be back again :D thanks:D
  8. Dec 2, 2015 #7


    Staff: Mentor

    None of your questions say how much power you need to generate. If you only need to light a bicycle light, then yes it is possible. If you need to heat or cool your house with a hand powered generator, then no thst is not practical.
  9. Dec 2, 2015 #8


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    Gold Member

    Actually, it's a lot better than that :smile:
  10. Dec 3, 2015 #9


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    Staff: Mentor

    Yes, that's how a bike dynamo works, and it is arranged that way so there is no requirement for sliding electrical connections---no commutator or sliprings. A bike dynamo when powering lights makes the bike significantly harder to pedal. In the era when I rode to school the typical bike dynamo rating was 6.3V 2.1A. IIRC
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