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Homework Help: Angular velocity help

  1. Aug 8, 2010 #1
    1. The problem statement, all variables and given/known data

    [PLAIN]http://img707.imageshack.us/img707/2066/question3.jpg [Broken]

    2. Relevant equations

    v = r' [tex]\hat{r}[/tex] + r*θ' (^θ)

    3. The attempt at a solution

    I was sure I knew how to do this question but made a mistake somewhere, because my answer is not right. So here is my working out.

    l r' l = 11mm/s
    Θ' = ?
    r = 78mm

    Looking at the question above.

    [PLAIN]http://img20.imageshack.us/img20/8729/lolbo.jpg [Broken]
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 9, 2010 #2

    ehild

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    Homework Helper

    Re: Velocity

    The angular velocity is usually given in radian/s. Check the answer in your book. Otherwise your result looks OK.

    ehild
     
  4. Aug 11, 2010 #3
    Re: Velocity

    There are two answer rads/s and degs/s, both are not the same as my answer.

    I definitely did something wrong.
     
  5. Aug 11, 2010 #4

    ehild

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    Re: Velocity

    The sign can be wrong. The velocity shown makes the angle θ smaller.

    ehild
     
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