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Can someone please help with this question

  1. May 24, 2006 #1
    Im studying year 12 physics and im a bit stuck with this question:

    The Earth is in its orbit around the sun. The mass of the earth is 6*10^24kg and the radius of its orbit is 1.5*10^11 metres

    Question wants me to find the magnitude of the momentum
    Im missing something, and i cant seem to remember how to do it,
    any help is appreciated,

    thanks,:confused: :uhh:
  2. jcsd
  3. May 24, 2006 #2


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    Homework Helper

    Start with the formulae for gravitational force and centripetal force.
  4. May 24, 2006 #3
    It's a bit simple, as Curious said, start with equating the gravitational and centripetal forces, then substitute in the momentum formula.
  5. Jul 12, 2006 #4
    Need to know the mass of the Sun so that the equation of centripetal force with Sun's gravitational force gives you Earth's orbital velocity, which then can be used to find Earth's momentum.
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