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Homework Help: Nonuniform Circular Motion

  1. Dec 8, 2007 #1
    I've come back once more with a question.

    -A hawk is flying along a horizontal arc (the path it takes is similar to a semicircle), in which the radius is 12.0m and the tangential acceleration is 1.20 m/s^2.
    All that has to be found is the net acceleration.

    -I know that the centripetal acceleration is constant (otherwise it most likely wouldn't be a circle) and the tangential acceleration is constant. So the the centripetal acceleration and tangential acceleration must be components of the net acceleration. How would I solve for the centripetal acceleration?
     
    Last edited: Dec 8, 2007
  2. jcsd
  3. Dec 8, 2007 #2

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    You are wrong. The centripetal accn is v^2/r, and if r is const but v is not, it's not const.

    Do you know the expression for tangential and normal accns? Use the formula:

    a = (dv/dt)T + (v^2/r)N, where T is the unit tangent vector and N is the unit normal vector.
     
  4. Dec 8, 2007 #3
    I see. So v^2/r applies even to nonuniform circular motion...
     
  5. Dec 8, 2007 #4

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    From the given value of dv/dt, find v. You may have to make some assumptions.
     
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