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Definition of the joule

  1. Nov 1, 2008 #1
    This is really basic, but I can't seem to find that one piece of reasoning that I must be missing...

    I don't understand the definition of the joule; 'the energy given to a body if a force of 1N is applied for the distance of one meter'

    If I apply 1N to an object of mass 1000kg until it has moved one meter, will I not have given it more energy than if I do the same to an object of 1 kg?

    edit: oops, didn't mean to post it in learing materials... sorry.
    Last edited: Nov 1, 2008
  2. jcsd
  3. Nov 1, 2008 #2


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    Hi mudkip9001! :smile:
    ah … interesting question …

    v2 = 2as, and so W = Fs = mas = mv2/2 …

    they have the same energy because the heavier mass is moving much slower :wink:
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