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Help on Gravity stuff

  1. Dec 9, 2008 #1
    1. The problem statement, all variables and given/known data

    Use Newton's law of universal gravitation to find an equation where x is equal to an object's distance from Earth's center, and y is its acceleration due to gravity. Use a graphing calculator to graph this equation, using 6400-6600 km as the range for x and 9-10 m/s2 as the range for y. The equation should be of the form y = c(1/x2).
    (a) Trace along this graph and find y at sea level, 6400 km.

    (b) Trace along this graph and find y on top of Mt. Everest, 6410 km.

    (c) Trace along this graph and find y in a typical satellite orbit, 6500 km.

    (d) Trace along this graph and find y in a much higher orbit, 6600 km.

    i got no idea how to solve any help or the answers would help greatly
  2. jcsd
  3. Dec 10, 2008 #2
    For a start you could read

    G= universal gravitational constant
    M = mass of earth (a constant)
    m = mass of your object (a constant)
    g = gravitational acceleration experienced by the object (a variable)
    r = distance of object from the centre of the Earth (a variable)

    G*M*m/r*r = m*g

    << complete solution deleted by berkeman >>
    Last edited by a moderator: Dec 10, 2008
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