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A 10 meter graphene pulley with 10,000 teeth, attached to a second graphene pulley of 10mm with 10 teeth both in a low temperature vacuum chamber.

The first graphene pulley is being rotated by a powerful motor powered by nuclear energy. Rotating at 300,000 RPM. Wouldn't the second pulley rotate faster than the speed of light?

(2Pi * 10M /60s) *300,000RPM = 314,159m/s. Since it's attached to 10mm with 10 teeth. It means every one revolution of the first pulley, the second pulley would rotate 1,000 times. So, 314,159m/s * 1,000 = 314,159,265m/s.

Where is the impracticability in the above solution?

king amada
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    not possible due to Ehrenfest paradox https://en.wikipedia.org/wiki/Ehrenfest_paradox also, any materials known would shatter long before relativistic speed, also it would take infinite energy, not nuclear power – Adrian Howard Sep 21 '19 at 23:21
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    Welcome New contributor king amada! Except for the details, is there any significant difference between your question and the frequently duplicated question here regarding rotating a long rod so the end exceeds the speed of light? – Alfred Centauri Sep 21 '19 at 23:25
  • Why complicate this with two "pulleys" which are actually "gears" with teeth, when the only relevant fact is the (alleged) FTL tangential speed of the rim of the large wheel? – alephzero Sep 22 '19 at 00:14
  • @AdrianHoward I don't think it would take infinite energy to rotate a 10 meter graphene pulley at 300,000 rpm. We have wind turbines that are more than 50 meters. A nuclear plant can produce over 1000MW, which means over 280 wind turbines. So if each wind turbine rotates at 20rpm, whilst the gearbox multiplies it to 1600rpm, multiply it by 280, would give you 448,000 rpm if you're to use nuclear power plant. So the only limitation I guess is the Ehrenfest Paradox as you point out. – king amada Sep 22 '19 at 04:34
  • @AlfredCentauri It's not duplicate of that question, as mine talked about using 10 meters of pulleys which is reasonable size to experiment with than 2000M in that question that you linked. We already have some small motors going at more than 300,000rpm. So attaching 2000m bar to a motor that spins that fast isn't reasonable and impractical. 10 meters graphene blade is really practical ad can be experimented with. Also since graphene is 2D particle I don't think Ehrenfest paradox will apply to it. What do you think? – king amada Sep 22 '19 at 04:40
  • @King amada: as energy of acceleration increases mass, mass approaches infinity as it approaches speed of light, so it would take infinite energy to reach it., per theory of relativity – Adrian Howard Sep 22 '19 at 06:26
  • also your math is incorrect the teeth on both gears would move at the same speed as they are meshed. you are incorrectly multiplying the smaller gears speed by 1000, because it is 1000 times the rpm, but it is a smaller radius – Adrian Howard Sep 22 '19 at 06:50

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