Tippe top: Mystery of the top
<FONT COLOR=FFFFFF SIZE="-1">Christian Friedl,</FONT> André Wobst, 2005/05/25, 05:41 PM
Mystery of the top
From the very complicated equations of motions follows that the quantity
G = r Lz - a L3
changes its magnitude very slowly. So we call it an "quasi-conservation quantity". (If there is no contact area, the above quantity would be exactly constant!) Note that as a consequence of the transition on the stem, there is an "parameter change" (i.e. a becomes a', r becomes r' and G changes to G'). One can show however, that G' and G are almost equal.
The amazing existence of an conservation quantity (when we speak from an "integral of the motion" or "the conservation quantity" we always mean our "quasi-conservation quantity") leads us ...
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