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Homework Help: Angular acceleration - Please check if this is correct and

  1. Nov 15, 2011 #1
    Angular acceleration - Please check if this is correct and....

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

    Question:

    Each of the tires of a car makes 85.0 revolutions as the car reduces its speed uniformly from 90.0 km/h to 60.0 km/m, The tires have a diamater of .900m.

    Find initial and final angular Velocities

    Find the angular acceleration of tires in rad/s^2

    My answers: Please tell me if thats right, because I have NO idea if its correct.

    awu9at.jpg

    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Nov 16, 2011 #2
    Re: Angular acceleration - Please check if this is correct and....

    If I am interpreting your work correctly, you are changing the km to m by multiplying by 900 instead of by 1000.

    I think that the rest is OK.
     
  4. Nov 16, 2011 #3
    Re: Angular acceleration - Please check if this is correct and....

    Oops lol

    Where whereever I have 900, change to 1000 correct? Just to be sure :)

    Because when I change that, I get -1.60 is that correct for this question?

    Because someone told me they got -4.88 ?
     
    Last edited: Nov 16, 2011
  5. Nov 17, 2011 #4
    Re: Angular acceleration - Please check if this is correct and....

    I got angular acc = -1.605rad/sec^2.
     
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