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Homework Help: What is the gravitational Field?

  1. Sep 10, 2008 #1
    Hint: Use shell theorem and/or flux argument for a symmetrical shell.

    A thin spherical shell has a radius of 3.4 m and a mass of 456 kg. The Universal gravitational constant is 6.6726 x 10^-11 N m^2/kg^2.

    What is the gravitational field 1.4 m from the center of the shell? Answers in units of N/kg.

    Attempt--
    I tried this equations, a= - G(delta m)/ (x^2 + y^2)
     
  2. jcsd
  3. Sep 10, 2008 #2
    forget equations. picture the flux
     
  4. Sep 10, 2008 #3

    LowlyPion

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    Homework Helper

    The gravitational field is a vector field. The gravity at the center will be the integral of all the mass of the shell acting at that point through all directions.

    Maybe read up a little about the Shell Theorem?
    http://en.wikipedia.org/wiki/Shell_theorem
     
  5. Sep 10, 2008 #4
    wait..is the answer zero?
     
  6. Sep 10, 2008 #5
    yip.
     
  7. Sep 10, 2008 #6
    eh.. thanks lol! Need to pay attention in class a bit more :)
     
  8. Sep 10, 2008 #7

    LowlyPion

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    Homework Helper

    Correctamundo.

    Good luck.

    Study Tip: Read next week's problems before going to next week's class. Then you know what part of the lecture to snooze through.
     
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