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Lifting Problems

  1. Apr 5, 2013 #1
    1. The problem statement, all variables and given/known data

    Find the work done in winding up a 150 ft cable that weighs 4.00 lb/ft. Assume that the weight includes the gravitational force. In order words exclude the gravitational force g in your calculation.

    2. Relevant equations

    W = ∫ pgA(y)D from a ft to b
    a = area
    P = density
    g = gravitational
    d= lifting distance


    3. The attempt at a solution
    The question clearly states that g should be excluded from the equation.
    W = ∫A(y) (d) from 150 to zero

    But I am not sure of my work.
     
  2. jcsd
  3. Apr 5, 2013 #2
    Finally found a solution to the problem.
    W= ∫ py dy from 0 to 150
    p = 4

    W = 4∫ ydy
    W = 4[y^2/2]
    W = 4 [11250] = 45000

    I Think this is the right answer to the problem.
     
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