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Homework Help: Oribital Radius

  1. Nov 2, 2004 #1
    How do you find an orbital radius of an object around earth with its mass and Orbital Period?
  2. jcsd
  3. Nov 2, 2004 #2
    Last edited by a moderator: May 1, 2017
  4. Nov 2, 2004 #3
    Awsome, thx man. Some of these equations ive never seen before help alot lol
  5. Nov 2, 2004 #4
    Never doubt the power of Mr.Google! :tongue2:

  6. Nov 2, 2004 #5
    Kenetic/Potential Energy

    When an object eaves the surface of the ground with a certain amount of Kenetic Energy and reaches a max height what does the Potential energy equal to?

    I know the equation Ep = -Gmm/r but the question says it leaves the surface with 15 J of Kenetic energy.
  7. Nov 2, 2004 #6
    When it reaches a max height, what happens to the kinetic energy?
  8. Nov 2, 2004 #7
    It equals 0?

    Does that mean potential energy is equal to it? or negative?
  9. Nov 2, 2004 #8
    The potential energy at its max height is equal to the amount of kenetic energy the object has just after it leaves the ground
  10. Nov 2, 2004 #9
    What about in orbit? How do you solve for Ep when you have Ek if you know the acceleration due to gravity and the mass?
    Last edited: Nov 2, 2004
  11. Nov 2, 2004 #10
    In orbit with constant velocity? or is it accelerating? In space, there is no acceleration due to gravity because there is no gravity.
  12. Nov 2, 2004 #11
    Its orbiting the earth, and is at a point where gravity is equal to .233 m/s²
  13. Nov 2, 2004 #12
    I believe the equation you're looking for is:
    Gravitational Potential Energy U = mg ( yf - yi ) = mg y

    However, I'm not quite sure what you're asking
  14. Nov 2, 2004 #13
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