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Astronomy - aphelion/perihelion from conservation

  1. Nov 6, 2006 #1
    Hi all,

    I'm stuck on this question for my assginment...i need to derive the velocity at perhelion and aphelion using two separate methods: the conservation of specific angular momentum and energy.

    I think I'm OK with the energy part but I'm stuck on getting the velocities at aphelion and perihelion using the conservation of specific angular momentum. If you guys can help me out it'd be great! Thanks.
  2. jcsd
  3. Nov 7, 2006 #2


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    Angular momentum magnitude is just rmv when the velocity is perpendicular to the vector r.
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