6A20.37 - Mirrors - Pendulum and Hemispherical Mirror

Code Number:
Demo Title:
Mirrors - Pendulum and Hemispherical Mirror
Concave, Convex Mirrors, Focal Lengths
Area of Study:
"Virtual Reality Mirror".

The "Virtual Reality Mirror" is an interesting variation.  It is a 8 inch diameter hemispherical mirror that is silvered on both sides for concave and convex demonstrations.  A dizzying effect is to suspend a ball at the center of the mirror and set it to swinging into and out of the mirror in pendulum fashion.  Watching the image during this process can bring about interesting individual reactions.

  • John W. Jewett Jr., "Bringing (Century-Old) Technology into the Classroom, Part II: Teaching Vibrations and Waves, Electricity and Magnetism, and Optics with Antiques", TPT, Vol. 54, #1, Jan. 2016, p. 24.
  • Borislaw Bilash II and David Maiullo, "Inside Up, Outside Down", A Demo a Day: A Year of Physics Demonstrations, p. 334.
  • Bobby Mercer, "Flash of Color", Junk Drawer Physics, p. 107.

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