8B40.20 - Black Hole Surface - Fiberglass or Plastic

Code Number:
8B40.20
Demo Title:
Black Hole Surface - Fiberglass or Plastic
Condition:
Good
Principle:
Black Holes, Gravity Well
Area of Study:
Stellar Astronomy
Equipment:
Fiberglass and Plastic "Wishing Well" Cones.
Procedure:

Use 1 inch ball bearings for the large Fiberglass cones.  Cones of 24 inch diameter and 40 inch diameter are available.  There will appear to be an event horizon just before the ball drops out of the cone and into the holder.

Use 1/4 inch ball bearings for the smaller (10 inch diameter) plastic cone.

References:
  • Harry Manos, "Making Inexpensive 3-D Models", TPT, Vol. 54, #3, Mar. 2016, p. 150.
  • R. D. Edge, "String and Sticky Tape Experiments: The Funny Physics Funnel", TPT, Vol. 28, #8, Nov. 1990, p. 575.
  • Katashi Nose, "Constructing a Potential Well-Hill for Overhead Projectors", TPT, Vol. 16, #7, Oct. 1978, p. 504.
  • L. Q. English and A. Mareno, "Trajectories of Rolling Marbles on Various Funnels", AJP, Vol. 80, #11, Nov. 2012, p. 996.
  • M. Kaan Öztürk, "Trajectories of Charged Participles Trapped in Earth's Magnetic Field", AJP, Vol. 80, #5, May 2012, p. 420.
  • "M-822. Garbage Bag - VORTX - Ball & String", DICK and RAE Physics Demo Notebook.
  • David Kutliroff, "49. An Inverse Square Law Force Field Sculpture", 101 Classroom Demonstrations and Experimenters for Teaching Physics, p. 109 - 111.
  • Robert Ehrlich, "B.3. Acceleration as an Effect of Curved Space-Time", Turning the World Inside Out, p. 17 - 20.
  • Robert Ehrlich, "B.2. Simulation of the Gravitational Deflection of Light", Turning the World Inside Out, p. 14 - 17.


Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.