1L20.30 - Escape Velocity (Escape from a Gravity Well)

Code Number:
Demo Title:
Escape Velocity (Escape from a Gravity Well)
Space Flight
Area of Study:
Solar and Galactic Astronomy
Gravity Well Demo and 1' Steel Balls.

See also 1L20.30 in Astronomy.

Set the demo up so that the end of the rail is in a horizontal position.  You want the steel balls to remain at the end and not roll back down.  Now using the spring accelerator you can demonstrate that a measured amount of force is needed for the ball to escape the gravity well (remain at the end of the rail).

Note: The spring accelerator is marked so that you can measure the amount of force that you want to apply.  To little force and the ball will fall back towards the spring accelerator (spacecraft will not achieve orbit).

  • Edward Ruth, "De-Orbiting Satellites Revisited", TPT, Vol. 55, #2, Feb 2017, p. 68.
  • Paul Hewitt, "Answer to May 2016 Figuring Physics", TPT, Vol. 54, #6, Sept. 2016, p. 372.
  • Paul Hewitt, "Answer to February 2016 Figuring Physics", TPT, Vol. 54, #3, Mar. 2016, p. 184.
  • Philip R. Blanco, Carl E. Mungan, "High-Speed Escape From a Circular Orbit", AJP, Vol. 89, #1, p. 72, Jan. 2021.
  • "M-815. Escape Velocity-Spoof", DICK and RAE Physics Demo Notebook.
  • Janice VanCleave, "30. Escape", 202 Oozing, Bubbling, Dripping, and Bouncing Experiments, p. 18.
  • Janice VanCleave, "94. Escape", Astronomy for Every Kid, p. 204 - 205.
  • D. Tattersfield, "2.21. Velocity of Escape", Project & Demonstrations in Astronomy, p. 30.
  • Robert Ehrlich, "8.11. Ball in a Rotating Single Well Potential", Why Toast Lands Jelly-Side Down, p. 133 - 134.

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