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Homework Help: I need help with some problems

  1. Mar 16, 2004 #1
    Hello, I am having a little problem understanding a problem it deals with energy. Here it is:

    You tell your friend that no machine can possibly put out more energy than is put into it, and your friend states that a nuclear reactor puts out more energy than is put into it. What do you say?

    Thanks in advance!
  2. jcsd
  3. Mar 16, 2004 #2
    Something along the lines of "No, it doesn't. Go do a bit of research about how nuclear reactors work." and, if I'm feeling generous that day, I might give them a link to start with. Like this one.


    And if I'm really feeling generous that day, I might explain it myself.

  4. Mar 16, 2004 #3
    Thanks for the answer, but I guess I did not clairfy what I needed. That problem was given to me, and we were told to explain it. We just finished learning about energy. And I am having trouble answering it. So if you oculd try to explain why that I would greatly appreciate it, but if not thanks anyway.
  5. Mar 16, 2004 #4

    Chi Meson

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    The answer has to do with the fact that a nuclear power plant is not a "machine." A machine is a device that manipulates an input force. A nuke plant is an "energy converter device" that takes the energy bound by uranium atoms and releases it. Compare that to a lever. Ever seen a lever go boom?
  6. Mar 16, 2004 #5
    Thank You So Much!
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