1. #1
    raaaid's Avatar Senior Member
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    you cant get an isolated system to acquire a rotation by itself

    false:

    http://www.youtube.com/watch?v=C4DfSBnBR08
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  2. #2
    Cajun76's Avatar Senior Member
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    Did you see the two men? It's not an isolated system...

    I was thinking today that we should have asphalt tires and rubber roads, and why this technology was being suppressed...
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  3. #3
    raaaid's Avatar Senior Member
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    the wheel and two men make an isolated system, the axle is free

    hey your opening your mind
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  4. #4
    Cajun76's Avatar Senior Member
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    The guys aren't static, they are using weight, muscle, momentum and inertia to affect changes.

    In no way, shape or form does this disprove CoM, at all.
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  5. #5
    raaaid's Avatar Senior Member
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    thats evident

    but cant you consider taking into account the free axel as the guys and wheel an isolated system?

    seems your deviating the subject

    edit:

    interesting concept this of wheel of death to build a perpetum mobile
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  6. #6
    Cajun76's Avatar Senior Member
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    Originally posted by raaaid:
    thats evident

    but cant you consider taking into account the free axel as the guys and wheel an isolated system?

    seems your deviating the subject

    edit:

    interesting concept this of wheel of death to build a perpetum mobile
    The subject is an isolated system, which you've chosen to redefine.

    "A system that does not interact with its surroundings, that is, its total energy and mass stay constant."

    As was clearly demonstrated, the men added mass, muscle, momentum and inertia to affect changes. They worked, they expended energy, they would be incapable of performing forever.

    I'm not deviating, I'm correcting an erroneous assumption. But rather than questioning your own assumption, all of physics must be wrong...
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  7. #7
    raaaid's Avatar Senior Member
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    nobody says in an isolated system you cant burn things

    the point is that to a motion in onse sense theres no contrary since the axle is free, second principle
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  8. #8
    Outlaw---'s Avatar Senior Member
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    BY DEFINITION an "isolated system" CONSERVES MASS AND ENERGY. If any individual system does not do so, THEN IT IS NOT AN ISOLATED SYSTEM.

    An "isolated system" DOES NOT EXIST IN REALITY. It can be approximated but never achieved.

    Simply enclosing some volume with an imaginary boundary does not suddenly make it an "isolated system".

    Regardless, momentum can do whatever it wants inside the system, it's energy that must be conserved. In this case, taking the initial state of the system as the total energy of the humans you can approximate a closed system. Some of the energy of the humans is transferred to the wheel. Much is lost as heat due to friction (in the bearings and aerodynamic drag). More is lost to heat in the conversion from chemical to mechanical. If you capture every Btu of heat lost by the humans and all the mechanical losses, it will equal the energy that was imparted to the wheel (to speed it up and slow it down). Of course there is work expended on the support frame to hold it in place but, like I said, it's an approximation.

    --Outlaw.
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  9. #9
    raaaid's Avatar Senior Member
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    the truth is im unsure cause in the end this is like a hamster wheel

    but an isolated system BOTH energy and momentum are conserved

    for example in the isolated system the universe is net momentum is zero and you cant change this

    but this guys control at will the momentum of a quite isolated system, just lake a running hamster
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  10. #10
    VW-IceFire's Avatar Senior Member
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    Originally posted by raaaid:
    the truth is im unsure cause in the end this is like a hamster wheel

    but an isolated system BOTH energy and momentum are conserved

    for example in the isolated system the universe is net momentum is zero and you cant change this

    but this guys control at will the momentum of a quite isolated system, just lake a running hamster
    Correct me if I'm wrong but those guys scarfed down several hot dogs before they started doing the work and therefore the system isn't isolated because in fact several hot dogs were consumed and their energy is now being put to good use... yes ?
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