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Homework Help: Angular Momentum hmmmm?

  1. Nov 29, 2004 #1
    Hi, can anyone help me get started on this problem...I am totally lost and dont know what equation to use...thanks a lot

    There is a moon orbiting an Earth-like planet. The mass of the moon is 6.23 x 10^22 kg, the center-to-center separation of the planet and the moon is 649000 km, the orbital period of the moon is 29.3 days, and the radius of the moon is 1040km. What is the angular momentum of the moon about the planet.
  2. jcsd
  3. Nov 30, 2004 #2
    they are talkin about point mass angular momentum

    L = r x p (the linear v is 90 degrees to the radius therefore) = r*p while p = mv and u can figure out the linear veloctiy useing the orbital period.

    29.3 days to go 2pi radians so... w = 2pi/(29.3 days) and v = wr so u get...

    L = r^2 m (2pi)/(29.3 days)
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