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Relativistic electrical varialbes

  1. Oct 20, 2012 #1


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    1) How does the electric circuit variables such as Voltage, Electric current, and Resistance vary between two frame of references?
    2) Based on (1): If someday we build a spaceship that move with very high speeds, are there issues to consider regarding the electric circuits in the ship?
  2. jcsd
  3. Oct 20, 2012 #2


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    https://www.physicsforums.com/showthread.php?t=631446#post4049887 might be of some interest, in that it shows a relativistic boost of a current loop. I'm not sure how clear it will be unless you're already familiar with the Loretnz transform and the charge-current 4 vector.

    Of course, there won't be any impact from any of this on a spaceship that moves at very high speeds -this follows directly from the principle of relativity. If there was any such effect, you could distinguish "rapidly moving" spaceships from "stationary" ones in an absolute sense. Relativity prohibits this, and thus even a rapidly moving spaceship won't see anything different as far as the laws of physics go. In fact, there are probably a number of observers that regard you as rapidly moving, right now.
  4. Oct 20, 2012 #3
    This is a very important topic which didn't get much attention
    as did 'twin paradoxes'. If speed affects length and time, and current is dependent on time,
    detailed analysis may show breakdown of Ohm's law on the ship as seen from earth.
    But Ohm's law will be obeyed as seen by an observer on the ship.
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