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Homework Help: Please help me on this problem

  1. Oct 11, 2004 #1
    I was doing my homework for my physics class, but now I am stuck at two questions and don't know what to do. :( And I don't know where to start. If someone can get me started and little tips on how-to-solve this question, that'd be awesome! :D

    If someone can help me solve this problem, I'd be really greatful! :) And I am glad that I found such a wonderful forum.

    Thank you. :)
    An elevator starts from rest with a constant upward acceleration and moves 1min the first 1.9 s. A passenger in the elevator is holding a 4.4 kg bundle at the end of a vertical cord. The acceleration of gravity is 9.8 m=s2 :What is the tension in the cord as the elevator accelerates? Answer in units of N.
    Last edited: Oct 11, 2004
  2. jcsd
  3. Oct 11, 2004 #2


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    Can you figure out how fast the elevator is accelerating?
  4. Oct 11, 2004 #3
    [tex] s=ut+\frac{1}{2}at^2[/tex] to find the constant upward acceleration,a.
    Use Newton's 2nd Law to find the tension :
    Upward direction is choosen to be positive, downward direction to be negative.
  5. Oct 12, 2004 #4
    Thank you both of you for answering the question. :)

    I actually tried couple of approaches and I discovered Leong's method is the best one and did it. :)

    Thanks again for the help!
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