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Homework Help: Floating logs and elevators

  1. Oct 16, 2006 #1
    hi guys.. can i ask you about this problem?
    A log is floating on swiftly moving water. A stone is dropped from rest from a 75meter high bridge and lands on the log as it passes under the bridge. If the log moves with a constant speed of 5 meters per second, what is the horizontal distance between the log and the bridge when the stone is released?
     
  2. jcsd
  3. Oct 16, 2006 #2
    A cable lifts a 1200kilogram elevator at a constant velocity for a distance of 35 meters. What is the work done by:
    a.) the tension in the cable
    b.)the elevators weight?
     
  4. Oct 16, 2006 #3

    Astronuc

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    Staff Emeritus
    Science Advisor

    Please post homework problems in the appropriate homework sections, e.g. Introductory Physics.

    Weight is nothing more than m*g, where m is mass and g is acceleration due to gravity. Work is the integral of force over distance, or simply product of force * distance, if force is constant over the distance.
     
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