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More tension prolbmes

  1. Feb 15, 2007 #1
    More tension prolbmes!!!

    1. The problem statement, all variables and given/known data

    A 4.95 kg object is attached to a vertical rod by two strings. The object rotates in a horizontal circle at constant speed 7.25 m/s. the lenght of both strings is 2.00m and the lenght of the verticle rod is 3.00m.

    (a) Find the tension in the upper string.
    (b) Find the tension in the lower string.

    2. Relevant equations

    equation for radius: r^2=c^2 - b^2

    3. The attempt at a solution

    radius equals 1.32m
  2. jcsd
  3. Feb 15, 2007 #2


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    Gold Member

    If i could have a picture of the set or something..
  4. Feb 15, 2007 #3
    I could not copy and past the pic...it wouldn't let me paste it on here. It's pretty much a verticle rod with a string coming from the top and the bottom corners to form a triangle. That's the best way I know how to depict it. Sorry
  5. Feb 15, 2007 #4


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    Gold Member

    You can upload the image by going to http://imageshack.us, and clicking "Browse". Then just locate the image on your hard drive and press upload. Use the link you are given to show the picture.
  6. Feb 15, 2007 #5
    Last edited by a moderator: May 2, 2017
  7. Feb 15, 2007 #6
    Hope this helps us all out...I know I need it!
  8. Feb 15, 2007 #7
    What is the centripetal force?
  9. Feb 15, 2007 #8
    the cent. acceleration is v^2/r. Which is 19.6^2/10=38.416
  10. Feb 15, 2007 #9


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    Homework Helper

    The problem is pretty straight forward. The acceleration only has one component which is the radial one, so the speed is constant. Use trigonometry to find the radius and to set the component of the tension in the direction of the radial acceleration.
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