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I Electromagnetic propulsion. (Not?)

  1. Aug 4, 2015 #1
    Hi folks,

    This is such a simple idea that I know I can't be the first to think of it so there has to be a "gotcha". Maybe an induced electric field working in the opposite sense??? Is there a kind soul out there who can spare a few moments to educate me after reading what follows? Thanks

    About 40 years ago I asked myself if one could take advantage of the light speed propagation delay and came up with this:

    http://andersson-design.s3.amazonaw...n the face of conservation of momentum. Bob.
  2. jcsd
  3. Aug 4, 2015 #2


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    You could look up 'Linear Motors for Rail Transport " and "Rail gun". All you need to do is to set up a travelling wave of magnetism along a track and your projectile / locomotive will follow it.
  4. Aug 4, 2015 #3
    Thanks for the prompt response: my childhood hero was Eric Laithwaite. But the effect I'm describing and seeking help with is the apparent, and hence rather unlikely, violation of conservation of momentum as all that's needed for the "motor" described above is that the electromagnets are held a fixed distance apart. The whole assembly can be in space, for example. So I'm missing something - either an effect that negates any thrust or a balancing radiation emission.

  5. Aug 4, 2015 #4
    How do you keep the electromagnets a fixed distance apart?
  6. Aug 4, 2015 #5


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  7. Aug 4, 2015 #6
    Hi nasu,


  8. Aug 4, 2015 #7
  9. Aug 4, 2015 #8


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    lol at bob nice simple answer =)

    EM is definitely the way to go though just about everything in the universe revolves around it =)

    When NASA fired a laser through it the particle's were faster than the speed of light is this true how can a magnetic field propargating at the speed of light propel laser light faster than the speed of light ??
    Last edited: Aug 4, 2015
  10. Aug 4, 2015 #9


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    I don't know the answer, but I bet you'd have to include things like mutual induction, which would probably act to stop this from happening the way you're thinking it would.
  11. Aug 4, 2015 #10


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    EM Drive is nonsense, and is specifically listed in the PF Rules as a Forbidden Topic. Thread is closed.

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