Lu, "
inertia force" is another way of referring to an "
apparent force". You quoted Prof. Berme as saying that the "
inertia" force is added to ensure equilibrium. If you consider an object moving in a circular path to be in equilibrium, then you are using a rotating reference frame. This is precisely the same as every argument I've given.
Physicists don't disagree on this. If physicists disagreed with biologists on the name of something smelly and slimy, would that mean that the biologists are wrong? NO. Trust those whose expertise is the field you're arguing.
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Flight Safety there's no stored energy in the way which you are referring on an object moving in a circular path. You can apply an accelerating force to a moving object without changing the object's kinetic energy. Consider a hockey puck moving north. Apply a force of the appropriate magnitude to the southwest and you can get the puck moving west and the same speed. You can't disagree that smacking a puck with a hockey stick causes an 'accelerating' force. Oh, you live in Dallas. Oops.
You asked, "
How can there be "continual acceleration" of the object in motion without any momentum changes (assuming constant speed)?"
There
are momentum changes. Momentum is a vector. A change in the magnitude, the direction, or both is caused by an acceleration. In the case of uniform circular motion, the magnitude of momemtum doesn't change, but the direction does.
No
Work is being done on the object because it's motion is perpindicular to the applied force.
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Dave, you're having too much fun with this one. <img src="smile.gif" border="0"> The string won't last forever so the experiment is finite. Besides, the net energy change is zero.
[ 24 December 2001: Message edited by: heedm ]</p>