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Difference between rule and law in physics

  1. Feb 13, 2013 #1
    Why is it that Newtons laws of motion and not Newtons rules of motion?
    Why is it that Fleming's right hand rule and not Fleming's right hand law?
  2. jcsd
  3. Feb 13, 2013 #2


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    From wiki:


    I don't think "scientific rule" is any different from a law.
  4. Feb 13, 2013 #3


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    I do: a rule would just be a convention.
  5. Feb 13, 2013 #4
    Toss Fermi's Golden Rule in there too. Newton's Laws, but Einstein's postulates, and Heisenberg's principle. I can't think of other names for laws, can you? Some don't even get any designation, like Hubble expansion. The pattern is, there is no pattern.
  6. Feb 13, 2013 #5
    It's clear from the definitions and examples of both words that a rule governs what a physicist should do to determine something and a law is a description of what nature will do. Newton's Laws tell us what objects in motion do. Flemming's Rule tells us what physicists should do to to determine the directions of field, current, and motion.
  7. Feb 13, 2013 #6


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    Russ is right.

    Laws explain how physical things behave under certain conditions.

    Rules have to do with communicating with other people. If we all follow the same practices (right hand rule to figure out which direction of rotation is positive and which is negative, for example), then it's easier to understand what that negative sign actually means, etc.
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