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Homework Help: Comet passing the sun

  1. Feb 21, 2010 #1
    1. The problem statement, all variables and given/known data
    A comet passes the sun at a distance of closest approach R = 6 * 10^8 m and speed 8 * 10^5 m/sec. How long will it take to travel 80 degrees around its orbit from the point of closest approach.

    2. Relevant equations
    omega = velocity / radius

    3. The attempt at a solution
    Since we can get omega from the above information, I should only have to integrate omega and set that equal to 80 degrees (or 4/9 pi radians)
    omega = 8 * 10^5 / (6 * 10^8) or 1/750
    the integral of this makes 1/750t and set that equal to 4/9 pi radians so,

    t = (750 * 4 * pi)/9
    t = 1047.2 seconds

    I am not sure if this is the proper way of writing this equation and confirmation would be appreciated. Thanks in advance.
  2. jcsd
  3. Feb 22, 2010 #2


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    Science Advisor
    Homework Helper

    Hi Mastablade! :smile:

    (have an omega: ω and a pi: π :wink:)

    No, that's for a circular orbit.

    A comet goes round the sun in a very elongated ellipse.
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