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URL:  http://boards.fool.com/when-moving-a-rotating-mass-about-its-rotating-20413987.aspx

Subject:  Re: Anti-grav - or bend a rod... Date:  3/1/2004  3:33 PM
Author:  splotto Number:  228 of 242

when moving a rotating mass about it's rotating axix, the force is realized 90 degrees in the direction of rotation, right?

The angular velocity/angular acceleration vector points at 90 degrees from the radial line to the center of rotation.

so if i have a mass spinning "toward" from me, push one end of the axel "forward" or away from me, that end should tend to move up, right?

If I understand your question my answer is no. The force acting on the rotating object (like a string connectiong the ball to the rod represenative of the gravitational force) would not be altered by the simple rotation of the rod about the connection point (which represents the center of gravity of the attracting object). Assuming the attrating object is homogeneous and that the gravitational force doesn't alter with the rotation, then the force still moves from the center of the ball to the connection point on the rod.

In a imperfect system like a lab, the string would actually twist and exert a force on the ball as it deforms and returns during the twist. This would cause the ball the turn and deflect from it's original path purely from the error in the model. If you have a true force or a connection medium that could deflect without recovering, then the error would not appear.

Splotto

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