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- Thread starter abercrombiems02
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Second, without actually solving the problem right now, I would suggest trying to work things out in terms of your angular momentum.

If you have a plate spinning, its angular momentum will be about the Z axis. if the plate is wobbling, the angular momentum vector is now rotating (sweeping out a cone). When they say wobble rate, I would assume this to be the the time derivatave of PHI(L), where PHI(L) is the angle in the XY plane of the angular momentum vector. Your task would then be to find a relationship between dPHI(L)/dt and w. You might have to create a ficticious angle for the plate to wobble thru in order to do the calculations.

As with all the advice I give, I could be wrong, but thats how I would start the problem

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If Feynman had to spend a while getting it, I guess you don't have to feel too bad if you are stumped. I think he said the general equations for a rotating body are quite complicated. I never got past the mysterious "principle axes" and "moment of inertia" calculations, which I didn't like, because nobody could explain exactly what a "principle axis" really was. Some sort of mystical entity, it seems. There must be some kind of line integrals plus group theory to figure out the principle axes, but it must be really bad since apparently nobody wants to talk about it.

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