Up or down?
Tuesday, November 02, 2004
Tuesday, September 28, 2004
Up or down?
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.
Answer:
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.