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Typical speed

  1. Jan 25, 2008 #1
    What is a typical ("maximum") non-relativistic speed ?
  2. jcsd
  3. Jan 25, 2008 #2


    User Avatar
    Science Advisor

    You mean, before the effects of relativity become significant? I guess it depends how much error you're willing to accept in the Newtonian calculation. If you give a specific example of a case where relativity's prediction about something would be different from the Newtonian prediction, someone can give you the amount the two predictions would be different as a function of speed.
  4. Jan 25, 2008 #3


    Staff: Mentor

    With no additional information about the error tolerance or the exact application, I would would use .14c as a general cutoff. That gives you a 1% time dilation.
  5. Jan 26, 2008 #4
    Electrons in a metal wire travel at a few mm/s...
    Edit: ...and you know that magnetic field that current generate is due to a relativistic effect of electric field.
  6. Jan 26, 2008 #5
    Well, I'm limited to 55 mph where I live, but I confess that I sometimes exceed that limit ... :wink:
  7. Jan 26, 2008 #6
    So, be careful not to be electrically charged, or you have to say you are going at relativistic speeds :wink:
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