6A10.17 - Mirror Box Puzzle

Code Number:
Demo Title:
Mirror Box Puzzle
Angle of Incidence = Angle of Reflection for Plane Mirror
Area of Study:
Covered mirror box with 5 to 6 movable mirrors inside, Laser.

This is an educational test designed to reinforce the concept of angle of incidence = angle of reflection for plane mirrors.  The box has 8 holes in it.  It can be set up so the laser beam enters one of the holes and exits any of the other holes with the proper orientation of the desired amount of mirrors (up to 6).  Once this is set up the box is closed so that the students only see where the beam enters and exits.  The teacher will tell the students how many mirrors are in the box and their positions.  The students are also told that the laser beam is bounced off every mirror in the box.  The challenge for the students is to predict the correct orientation of the mirrors.  The box can then be opened to see whether their prediction is correct.

A commercial version of the mirror puzzle box with its own laser diode style lasers.

  • J. Christopher Moore and Louis J. Rubbo, "Modeling Hidden Circuits: An Authentic Research Experience in One Lab Period", TPT, Vol. 54, #7, Oct. 2016, p. 423.
  • Scott Miller, "Modeling the Nature of Science with the Mystery Tube", TPT, Vol. 52, #9, Dec. 2014, p. 548.
  • Dean Zollman, "Resolution: A Simple Demonstration", TPT, Vol. 12, #2, Feb. 1974, p. 89.
  • Jearl Walker, "6.67, A Sideshow Laser Shoot", The Flying Circus of Physics Ed. 2, p. 268.
  • Bobby Mercer, "Black Box", Junk Drawer Chemistry, 2016, p. 52.

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