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Homework Help: Circular Motion and Gravitation of asteroid

  1. Oct 12, 2011 #1
    The asteroid 243 Ida has a mass of about 4.0×1016 and an average radius of about 16 (it’s not spherical, but you can assume it is).

    A)Calculate the speed with which you would have to throw a rock to put it into orbit around the asteroid 243 Ida, near the surface. v= ?

    B)How long would it take for your rock to return and hit you in the back of the head? t=?

    Arad= v^2 / R

    v=2 pie R / T

    A rad= 4 pie^2 R /T^2

    Fnet= m (v^2/R)

    My brain is fried trying to figure out these problems since i missed lecture because i was sick. trying to submit this hw thats due in like 2 hours any help will be much appreciated!!!!
  2. jcsd
  3. Oct 12, 2011 #2


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    Staff: Mentor

    Units on your values would help. Is the radius 16m? 16km? 16 miles? How about the mass?
  4. Oct 12, 2011 #3


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    Gold Member

    1] You must use the template provided.
    2] You must show your attempts at a solution.
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