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Homework Help: Angular Momentum of an airplane

  1. Feb 24, 2006 #1
    An airplane of mass 12000kg flies level to the ground at an altitude of 10. km with a constant speed of 175 m/s relative to the earth. (a) what is the magnitude of the airplane's angular momentum relative to a ground observer directly below the airplane? (b) Does this value change as the airplane continues its motion along a straight line?

    desperate....was out with the flu now im lost :confused:
    so L= r X Mv....
    L=r??X (12000)(175)
    r=10??
    so 10X(12000)(175)
    21000000. this doesnt look correct...
     
    Last edited: Feb 24, 2006
  2. jcsd
  3. Feb 24, 2006 #2

    Hootenanny

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    What equations do you know that relate linear velocity with angluar momentum (assuming the earth is spherical)
     
  4. Feb 24, 2006 #3
    just edited first post. i guess maybe
    I=(2/5)Mr^2 might come in handy?
     
  5. Feb 24, 2006 #4

    Hootenanny

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    [itex] L = Mvr [/itex] would be easier to use with regards to the plane, where [itex] r [/itex] is the radius of orbit and v is linear velocity.
     
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