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Hello! I have a question on angular velocity

  1. Sep 6, 2014 #1
    1. Here is the equation http://i.imgur.com/EKdWnws.png

    2. The attempt at a solution
    The first part I've done correctly. So here's my thought process:
    To get the period I used T=2 * pi * sqrt(r3 /GM_E)
    T=5521s
    W(angular velocity)=2pi/T
    W=1.138*10-3 rad/s
    V=WR where r is 6754000m
    V=7686m/s
    Since the thrusters double the speed of the satellite v will be become twice that and the radius will be 15.9% more. Therefore:
    2V=W(R+R*15.9/100)
    Substituting in all the values I had to get W my answer was 1.964*10-3 rad/s.
    But I didn't get my answer right. I may have done the wrong process but it seems pretty logical from my perspective. Please enlighten me.
     
  2. jcsd
  3. Sep 6, 2014 #2

    Orodruin

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    The equation v = ωr is only valid for the tangential velocity (or the total velocity if the radial component is zero). After the craft has doubled its velocity, it will no longer have a circular orbit. You also cannot assume that the velocity will be constant with radius.

    To help you along: Do you know of any conservation laws that may be applicable?
     
  4. Sep 6, 2014 #3
    Can't really think of one. The only ones I know of are energy and momentum laws.
     
  5. Sep 6, 2014 #4

    Orodruin

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    So, the question becomes: Which momentum is conserved, linear or angular?
     
  6. Sep 6, 2014 #5
    I would say angular?
     
  7. Sep 6, 2014 #6

    Orodruin

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    That is a good start. So what expressions do you know that give the angular momentum? What is the initial angular momentum?
     
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