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Subj:     The Monkey and The Rope (S483c) 
          From: From: MathForm.org on 4/28/2006
Source: http://mathforum.org/rec_puzzles_archive/physics

Hanging over a pulley there is a rope, with a weight at one end.  At the other end hangs a monkey of equal weight.  What happens if the monkey starts to ascend the rope?  Assume that the mass of the rope and pulley are negligible, and the pulley is frictionless.

Monkey Drawing from
Yahoo Images
on 4/28/2006

Solution:

The monkey is pulling down on the rope hard enough to pull itself up.  This increases the tension in the rope just enough to cause the weight to rise at the same rate as the monkey, since they are of equal mass.

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