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Statics and Friction 01

  1. Jun 30, 2009 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    F = uR

    3. The attempt at a solution

    I don't understand the followings:

    For equilibrium at A, the equation should be F1 = T sin [tex]\theta[/tex]. Am I right?

    While for the one at B, the equation should be F2 = T sin [tex]\theta[/tex]. Am I right?

    In addition, how can I get cos [tex]\theta[/tex] = (au2 + 1)-0.5 at the last answer?

    Thank you very much!
  2. jcsd
  3. Jul 1, 2009 #2
    I tried some methods and found the followings finally:

    tan [tex]\theta[/tex] = 3u = 3u / 1

    Put the above result to a right-angled triangle with adjacent side = 1 and opposite side = 3u,

    we can get cos [tex]\theta[/tex] = (9u2 + 1)-0.5.

    I guessed that the "a" is actually a "9" which is a typo instead. Am I right?
  4. Jul 2, 2009 #3

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    You seem to be quite right.
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