1R50.24 - Crystals - Mirror Images and Symmetry

Code Number:
1R50.24
Demo Title:
Crystals - Mirror Images and Symmetry
Condition:
Excellent
Principle:
Crystal Formation and Structures, Symmetry and Mirror Images
Area of Study:
Mechanics
Equipment:
Mirror Image Crystal Models, Cloth Covered Board, Deck of Cards.
Procedure:

Show that the mirror images are not super imposable on each other.

Set the cards up on the board as shown.  It is easiest to start with 4 cards first and then fill in the quadrants with additional cards.  After the demo is set, you can knock on the table or the board and either get left or right handed chirality when the cards fall.

The turnbuckle has both right handed and left handed eye bolts.

Use the bolts with a mirror to help determine a mirror image.

References:
  • Martin Garder, "Physics Trick of the Month: Broken Symmetry", TPT, Vol. 38, #9, Dec. 2000, p. 564.
  • C. N. Yang, "Symmetry Principles in Physics", TPT, Vol. 5, #7, Oct. 1967, p. 311.
  • Johanna L. Miller, "Magnets Separate Mirror-Image Molecules", Physics Today, Vol. 71, #7, July 2018, p. 14.
  • Steven K. Blau, "Polarized Electrons See Mirrored Molecules Differently", Physics Today, Vol. 67, #11, Nov. 2014, p. 19.
  • Johanna Miller, "Macroscopic Chiral Crystals Can Segregate Themselves", Physics Today, Vol. 66, #10, Oct. 2013, p. 14.
  • Ashley G. Smart, "A Mirror Gives Light An Extra Twist", Physics Today, Vol. 64, #6, June 2011, p. 16.
  • Martin Gardner, "Twiddled Bolts", Smart Science Tricks, p. 44.
  • T. D. Rossing and C. J. Chiaverina, "#1, Screw Viewed In A Mirror", Light Science, Physics and Visual Arts, p. 302.

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