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Homework Help: Acceleration and velocity help

  1. Sep 17, 2011 #1
    In an equation a = v^n/r^m, a is the acceleration, v is the velocity and r is the radius of a circle. What are the values of n and m?



    1. n=3 and m=2

    2. n=2 and m=2

    3. n=1 and m=2

    4. n=2 and m=1

    5. n=2 and m=3


    The attempeted solution is:

    L/(T)^2 = v^n/r^m

    since Velocity is distance/time.
    L is the length
    T is the time.

    n=1 and m=2


    Thanx in advanced
     
    Last edited by a moderator: May 12, 2014
  2. jcsd
  3. Sep 17, 2011 #2
    Re: 1. The problem statement, all variables and given/known data

    That's not correct, but that's the way to solve it. Just think carefully of what you are doing.
     
  4. Sep 17, 2011 #3
    Re: 1. The problem statement, all variables and given/known data

    a = [m^2/s]

    v = [m/s]

    r = [m]

    how many [m/s]'s and [1/r]'s go into a [m^2/r]?
     
  5. Sep 17, 2011 #4
    Re: 1. The problem statement, all variables and given/known data

    @DiracRules Thanx for assuring that this is the right way to go.

    @zheng89120 I think you need to have a look at "a = [m^2/s]". Because I think it should be a = [m/s^2] instead. based on your next reply I'll start working.

    Thank you all for replying.
     
  6. Sep 17, 2011 #5
    Re: 1. The problem statement, all variables and given/known data

    with couple of trials with the same way of thinking, I found out that m = 1 and n = 2. If someone could only make sure of the answer.

    Thanx once more
     
  7. Sep 17, 2011 #6
    Re: 1. The problem statement, all variables and given/known data

    yes that is correct, AND by the way if you're taking any university level physics course, you should have the formula a = v^2/r memorized
     
  8. Sep 17, 2011 #7
    Re: 1. The problem statement, all variables and given/known data

    @zheng89120 Thank you very much for helping. And obviously you know more than what I do in physics. And I'll keep this formula [a = v^2/r] in mind ;)
     
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