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Hypothetical questions

  1. Jun 4, 2008 #1
    I know what most people think about reactionless drives and or inertial drives, but I still have some hypothetical questions about the latter.

    In most inertial drive setups there is usually a spinning flywheel of some sort that is balanced. Next the inventor trys to offset the balance for a very brief amount of time to create a unidirectional thrust.

    My questions overlook the fact that none of these devices have ever worked besides gyroscopic precession. Just play along for now that one of these devices does work as described.

    1. If you had a "thrust" of say 10 newtons 4 times per second, how would you figure out how much thrust/sec you have?

    2. If the flywheel is spinning at a given rate how many times could you cause a pulse (thrust) without stopping the wheel or slowing it to a rate that would be usless to your purposes?

    Sorry about all the make believe, but I get these things in my head and can't let go sometimes.

    Thanks for you patients, and if this is in the wrong place please...move it along!
  2. jcsd
  3. Jun 4, 2008 #2

    Vanadium 50

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    Your question makes no sense. It's asking a theory - in this case, the theory of mechanics - to make accurate calculations of things that it says are impossible. It's not even internally consistent.
  4. Jun 4, 2008 #3
    Okay, then.

    I'm sure those of you that are much smarter than me...(there are many), get where I'm going with this. If there are inconsistancies just point them out. I've already conceded that there are inherent problems with this type of system. I've asked two seemingly simple questions. If you don't want to answer that is fine. All I ask is that you just humor the ignorant. I'm not asking for a smack down.
  5. Jun 4, 2008 #4


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    For #1, thrust is force. Newtons. I guess you could calculate an average thrust. That might be useful.

    For #2, Vanadium is right - the question assumes the existence of something that doesn't exist. So I guess that means the answer is zero.
  6. Jun 4, 2008 #5

    Vanadium 50

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    If you asked us "how many sides does a square circle have", how would you expect us to answer? It's the same kind of built-in contradiction.
  7. Jun 4, 2008 #6

    Thanks for the effort.
  8. Jun 5, 2008 #7
    It just dawned on me that this forum is most probably not used to "what ifs". It is more geared toward solid proven methods and facts.

    So for that oversite I oppologise.
  9. Jun 6, 2008 #8
    I think you misunderstand the nature of their problem. They're not being stubborn or closed-minded. Basically what you're saying is something like "I know that Force = mass * acceleration but let's say for a second it didn't and I have a 1 kg mass with a 1 m / s^2 acceleration, what would the force on it be?". So in other words you're asking what result would physical theory predict if physical theory didn't apply.

    As for the average thrust well 10 N 4 times a second = 40 N / s
  10. Jun 6, 2008 #9


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    I believe it's a more fundamental problem than that. If one asks a hypothetical question that does not obey the fundamental laws, then one may choose any answer one wishes as there is no law to disprove it.

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