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Mechanical Resistance in a simple generator?

  1. May 6, 2012 #1
    Hallo everyone!

    I'd like to build a simple generator for a project.

    Like this picture here:

    http://www.interactives.co.uk/images/DSCN7717crr.JPG [Broken]

    I have everything I need but one think keeps coming into mind... Mechanical resistance?(Not friction due to material's touching each other like the conventional generator.) I'm building a generator exactly the same as the one in the image. The mechanical resistance I'm worried about is when I'm actually adding a "load" to the generator can I feel a mechanical resistance? Do I have to add more mechanical energy from my hand?

    If I'm applying simple mechanical energy from my hand when adding a load to the coils like a set of led's would I feel a mechanical difference by having a load or not?

    Hope I'm making sense... All in all I'm asking about Mechanical resistance if there is a load" light bulb's or small motor" attached to it.

    Thank you!
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. May 6, 2012 #2


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    Yes, a load will increace the work required to turn the handle. However, you may or may not be able to feel it.
  4. May 6, 2012 #3
    Is there a way to avoid it? Or its inevitable?

    How can I calculate that? I'd like to add more load's I'd like to calculate how much energy I need in to work the extra load.

  5. May 6, 2012 #4
    The work required is the same as the wattage of the load, where do you think that work would come from?
    Force times distance (and divided by efficiency) is wattage; so is resistance times current.
  6. May 6, 2012 #5


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    Wow! What an awesome illustration. Sorry that I can't help as much as the others as to electromotive drag (or whatever it's called), but I do have to ask you about your software. I've heard of, and seen examples of, Solidworks and similar things before, but could never possibly afford them. Is there any chance that this is something less expensive (and Mac compatible)?
  7. May 6, 2012 #6
    The mechanical resistance was my main problem, Whats the name of this resistance electromotive drag? or what?

    hahaha! Thanks about that but I'm sorry I didn't make this illustration I just got it from google.
    You could find a lot! Of good programs at a affordable price if you search for it and I grantee you its compatible with a Mac. Generally they state that. Thanks!
  8. May 6, 2012 #7
    The opposing force is called counter torque.
  9. May 6, 2012 #8


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    Ah, got it, Hypo. Thanks for the tip.
    If anyone thinks it hypocritical of me to have asked about this after having recommended Sourcforge to Gurudon for drawing software in a different thread, I must point out that the only stuff that they have of this nature is either in Beta or earlier version and/or not Mac-compatible. Believe me; I've downloaded a bunch of them.
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