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Faster than light theory #759309

  1. Oct 26, 2004 #1
    faster than light theory #759309....

    imagine a propeller from a helicopter...we know that the part of the blade farthest form the pivot point moves faster than the section nearest to the pivot point... so in theory, if we could get the section nearset to the pivot point to move close to the speed of light, then would the outer most section be moving at, or faster than the speed of light? (taking into consideration that we are using the strongest materials we have and it is well lubed etc etc.....) i'm not sure what purpose this would serve other than to get ones picture on the front of a science mag.... but n e way....
  2. jcsd
  3. Oct 26, 2004 #2
    no object is absolutely rigid as a consequence of special relativity. From an outsider's point of view, the blade would still be moving at a speed even nearer to the speed of light, when compared to the speed of the "section nearest to the pivot point".
    There is no such "strongest" material anymore.
  4. Oct 27, 2004 #3
    Even if you theoretically consider a very rigid material, you cannot get the outer section to be moving at a speed greater than or equal to that of light.
    Because in this case, the energy that you need to supply to the inner part would still exceed any amount of energy,since actually you are also providing energy to the outer part, if only indirectly.
  5. Oct 27, 2004 #4
    ahh..good answer..sigh...
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