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Homework Help: 2 questions from rolling motion

  1. Dec 21, 2016 #1
    • Poster has been reminded that the use of the HH Template and showing work is not optional
    Both the questions are at https://imgur.com/a/o7B20
    The problem I am facing is that on a straight line friction is there and I can't balance it. Using F=ma and T=Iw doesn't work.
  2. jcsd
  3. Dec 21, 2016 #2
    Knowing the mass of the ball and the coefficient of friction you know the force of friction, so you know what to put for Force and Torque. And don't forget that the ball is not constrained, so it gets torque and linear acceleration.
  4. Dec 21, 2016 #3

    Simon Bridge

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    Science Advisor
    Homework Helper

    Welcome to PF;
    The trick is to realise what kind of friction is between the rolling ball and the plank.
    Otherwise as above.
  5. Dec 21, 2016 #4
    But that's the problem I can't from those equations
  6. Dec 21, 2016 #5


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    Staff: Mentor

    This thread is closed because it doesn't comply with the PF rules for schoolwork posts. Please check your PMs, and re-post your question using the Homework Help Template and showing your work.
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