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Old 29th June 2008 | 15:44
  #33 (permalink)  
Matthew Parsons
 
Joined: Feb 2005
Posts: 340
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From: KPHL
pb, you are correct, that was my understanding of your thread. However, you did say that momentum was not conserved when the air goes down. However, the free falling mass increases its momentum and you contend that momentum is conserved in that case because the earth moves.

What if the free falling mass started hurtling small bundles of mass to the ground with sufficient effort that the large mass reduced its momentum to zero? Get my point?


Like I said, expand the view to a 3 dimensional model and conserving momentum become easy. Two vortices with equal and opposite angular momentum (for unaccelerated flight of course), job done.
This sounds like a gyro-levitation device (those don't work). If creating two equal and opposite vortices is the action, then the reaction is going to be two equal and opposite moments. That would sum to zero as well.
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