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Re: Physics Answer to a Question...



...
Case 3) He doesn't replenish (i.e., the rocket problem).
...
which gives 9,064 big ones as the result.


In spite of several claims to the contrary, this problem does NOT reduce
to the standard rocket problem, even when the old man's mass is allowed
to diminish. The reason is that the standard derivation of the rocket
equation requires taking a limit delta m --> 0, where "delta m"
represents the small amounts of mass being ejected. In the present
case the limit cannot be taken, and, as pointed out in an earlier post,
the resulting nonzero additional term is approximately of the same
magnitude as the "rocket" term. When both are in effect (i.e., when
the mass is allowed to diminish), only about 5000 "spits" are needed
to get to the desired 1 m/s.

A. R. Marlow E-MAIL: marlow@beta.loyno.edu
Department of Physics, Box 124 PHONE: (504) 865 3647 (Office)
Loyola University 865 2245 (Home)
New Orleans, LA 70118 FAX: (504) 865 2453