26 Nov
2010
26 Nov
'10
5:05 p.m.
On Friday 26 November 2010 22:17:54 Gary Antonick wrote:
As M/m approaches infinity the size of the extra small wedge approaches zero. Does this mean at the limit the two balls will have the same final velocity? If so, what is this final velocity? (And how is this scenario reversible?)
In the limit, the final velocity of both balls is zero. The bigger M/m is, the greater the fraction of the energy and momentum that ends up belonging to the bigger ball; as its mass tends to infinity, the corresponding velocity goes to zero. Of course a final velocity *equal* to zero makes for an irreversible scenario, but that's only the limit. In any actual case with finite M, the balls end up with unequal, nonzero final velocities. -- g