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Author Topic: Is this youtube videeo scientifically correct?  (Read 2019 times)

Offline jartza

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Is this youtube videeo scientifically correct?
« on: 12/03/2011 11:31:04 »
Speeds that the rods reach are relativistic

http://www.youtube.com/watch?v=oqa3HYkg5no



 

Offline yor_on

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Is this youtube videeo scientifically correct?
« Reply #1 on: 12/03/2011 17:14:48 »
If you rotate the rod too close to 'c' it will crack, the question seems to become which one it will be, your first rod, or the second one? And that seems to have to do with what speeds the first rod reach before the second one start to rotate, and also how the second rod is situated relative the motion, before it too starts to rotate?

You really like the difficult ones, don't you Jartza :)
 

Offline Soul Surfer

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Is this youtube videeo scientifically correct?
« Reply #2 on: 13/03/2011 11:37:45 »
Why should you say that jartza? your video has no explanations, dimensions materials, or statements of rotational velocity.

No part of a machine like that made from ANY material could remotely reach a relativistic velocity provided you defined relativistic velocity as a significant  fraction say 10% of the velocity of light.

However it is obvious that all velocities ARE relativistic if you place no lower limit it is just that any departure from non relativistic behaviour would be extremely small and almost ubdetectable
 

Offline syhprum

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Is this youtube videeo scientifically correct?
« Reply #3 on: 13/03/2011 11:41:34 »
The power rating of an electric motor bears no direct relation to its rotational speed this is mostly determined by it's detailed design
 

Offline Phractality

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Is this youtube videeo scientifically correct?
« Reply #4 on: 16/03/2011 13:52:33 »
I agree with Soul Surfer  [8D] completely, except it's more like .00001% instead of 10%. A flywheel in the form of a uniform steel disk has a maximum rim speed in the neighborhood of 300 to 500 m/s. (Any mechanical engineer can tell you, the size of the flywheel doesn't matter, the rim speed is the same for any shape and material.) Max rim speed for a flywheel made of carbon nanotubes with the theoretical maximum strength might be in the neighborhood of 1 km/s. To be generous, you might guess that the max rim speed is the speed of sound in the material, which is about 8,000 m/s for Kevlar. The speed of light is 300,000,000 m/s.  :o

So your motors can't be made of atoms. Maybe they're atomic scale motors, and the armatures are electrons. Still, you're on shaky ground assuming that relativity works at that scale. GR doesn't work at the quantum scale. In my own model, the Higgs force alters the path of light zillions of times more strongly than gravity does. Anything that bends light in Euclidean space causes the warp of Minkowski space time. So GR needs to be modified to include the warp due to the Higgs force if it is to work at the atomic scale.
 

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Is this youtube videeo scientifically correct?
« Reply #4 on: 16/03/2011 13:52:33 »

 

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