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Tension question

  1. Sep 23, 2004 #1
    Figure 5-58 shows a section of an airplane cable-car system. The maximum permissible mass of each car with occupants is 3000 kg. The cars, riding on a support cable, are pulled by a second cable attached to the support tower on each car. Assume that the cables are taut and inclined at angle = 35°. What is the difference in tension between adjacent sections of pull cable if the cars are at the maximum permissible mass and are being accelerated up the incline at 0.78 m/s^2?

    http://timelmore.ipupdater.com/05_55.gif [Broken]

    I don't even know how to get started on this, and neither does anyone else taking the class. The professor is out of town, does anyone have any thoughts or advice? Equations and theory would be nice- I'm not looking for someone to do my homework for me, as I know how to do othre tension problems, I just don't really know what tehy're asking for and how the angle plays into it.

    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Sep 23, 2004 #2

    Doc Al

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    Staff: Mentor

    Here's how I read the problem. The support cable supports the weight of the cars just as a frictionless incline plane would support a mass resting on it: it supplies a normal force. The pull cables, on the other hand, provide a force parallel to the cables that prevents the cars from sliding down and imparts some acceleration to the cars.

    So identify all the forces on each car and apply Newton's 2nd Law for components parallel to the cable.
  4. Sep 23, 2004 #3

    that's what I thought


    so, (3000*sin(35)*9.81)+(3000*.78)

    I could do it, the problem was just worded tough
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