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Homework Help: Equation Jeopardy (HW)

  1. Sep 26, 2005 #1

    jtm

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    Identify any errors in the solution to the following problem and provide a corrected solution if there are errors.
    The problem A 1000kg elevator is moving down at 6 m/s. It slows to a stop in 3 m as it approaches the ground floor. Determine the force that the cable supporting the elevator exerts on the elevator as the elevator stops. Assume that g = 10N/kg.

    Proposed solution The elevator at the right (picture) is the object of interest. It is considered a particle, and the forces that other objects exert on the elevator are shown in the free body diagram (T == F_e) The accelration of the elevator is:

    a = v_0^2 / 2d = 6^2 / 2(3) = 6.0 m/s^2
    The force of the cable on the elevator while stopping is:

    T = ma = (1000kg) * (6.0 m/s^2) = 6000N
     
  2. jcsd
  3. Sep 26, 2005 #2

    Tide

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    Science Advisor
    Homework Helper

    Does the gravitational force cease to act on the elevator while it's decelerating?
     
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