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Homework Help: 2 mp problems that I sorta understnad but dont?

  1. Mar 1, 2005 #1
    2 mp problems that I sorta understnad but dont??

    Edit: I figured out first problem... I was missing + pi/2 in the equation but still a little screwed up on second problem :

    Edit: Figured both of em out with help. thanks for the help
     
    Last edited: Mar 1, 2005
  2. jcsd
  3. Mar 1, 2005 #2

    Doc Al

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    Staff: Mentor

    Check your answer for [itex]\omega t = 90[/itex] degrees and see if your signs are correct. Note: Positive [itex]\omega[/itex] means it rotates counter-clockwise!
     
    Last edited: Mar 1, 2005
  4. Mar 1, 2005 #3
    Yeah I just got it before I read your post guess I was little stupid on that one heh.. but second one I still dont get what im doing wrong?
     
  5. Mar 1, 2005 #4

    dextercioby

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    [tex] \theta (t)=\theta(0)+\omega_{0}t+\frac{1}{2}\alpha t^{2} [/tex]
    [tex] \omega (t)=\omega(0)+\alpha t [/tex]

    That's all u have to use...Properly.Pay attention to signs & initial conditions...

    Daniel.
     
  6. Mar 1, 2005 #5
    dont need help anymore heh got both answerss I needed I feel quite stupid now actually heh
     
  7. Mar 1, 2005 #6

    Doc Al

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    OK.
    Not clear what you did. Use [itex]\omega_f = \omega_i + \alpha t[/itex]; be sure to use proper units for [itex]\omega[/itex].
     
    Last edited: Mar 1, 2005
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