1R20.11 - Stress - Elastic Limits

Code Number:
1R20.11
Demo Title:
Stress - Elastic Limits
Condition:
Good
Principle:
Stress & Tension
Area of Study:
Mechanics

Disclaimer

Equipment:
Wooden Dowel, Brass Spring Sections, and Plastic Meter Stick.
Procedure:

Exceeding the elastic limit can be done easily with springs and wooden dowels.  Cut several lengths of spring.  Regular spring action is observed until the spring is stretched beyond the elastic limit at which time it will no longer contract to it's original position.

The plastic meter stick may be bent full circle if desired.  The dowel can only be bent a small way before the elastic limit is exceeded and the dowel breaks.

References:
  • Bradley Allen, "From the Simple to the Surprisingly Complex – An Incremental Study of Elasticity", TPT, Vol. 57, #8, Nov. 2019, p. 570.
  • Issac-Cesar Aguilar and David Kagan, "Breaking  Bat", TPT, Vol. 51, #2, Feb. 2013, p. 80.
  • Rod Cross, "Elastic Properties of Plasticine, Silly Putty, and Tennis Strings", TPT, Vol. 50, # 9, Dec. 2012, p. 527.
  • Ligia R. Gomes, Ana Amado, Manuel C. Torres, and Luís M. N. B. F. Santos, "Simple Apparatus for Measurement of a Mechanical Properties of Solids", TPT, Vol. 49, #2, Feb. 2011, p. 117.
  • Bernard J. Feldman, "The Collapse of the I-35W Bridge in Minneapolis", TPT, Vol. 48, #8, Nov. 2010, p. 541.
  • Ivan Culaba and Ed van den Berg, "Tensile Stress and Shear Stress", TPT, Vol. 47, #2, Feb. 2009, p. 121.
  • Paul Hewitt, "Figuring Physics", TPT, Vol. 32, #2, Feb. 1994, p. 121.
  • James Casey, "The Elasticity of Wood", TPT, Vol. 31, #5, May 1993, p. 286.
  • D. L. Mathieson, "The Tensile Strength of Paper", TPT, Vol. 29, #6, Sept. 1991, p. 412.
  • R. D. Edge, "Strength and Shape", TPT, Vol. 25, #1, Jan. 1987, p. 50.
  • H. Richard Crane, "Stretch Orientation: A Process of a Hundred Uses", TPT, Vol. 23, #5, May 1985, p. 304.
  • R. D. Edge, "Elasticity", TPT, Vol. 21, #9, Dec. 1983, p. 608.
  • Jeffrey May, "Physics on a Dinner Plate", TPT, Vol. 18, #9, Dec. 1980, p. 668, also A Potpourri of Physics Teaching Ideas - Sound, p. 251.
  • Joseph Gallant, "The Shape of the Eiffel Tower", AJP, Vol. 70, #2, Feb. 2002, p. 160.
  • Lucas Goehring and Stephen W. Morris, "Cracking Mud, Freezing Dirt, and Breaking Rocks", Physics Today, Vol. 67, #11, Nov. 2014, p. 39.
  • Janice VanCleave, "17, Weakened", Engineering For Every Kid: Easy Activities that Make Learning Science Fun, p. 119.
  • Janice VanCleave, "16, The Limit", Engineering For Every Kid: Easy Activities that Make Learning Science Fun, p. 113.
  • Jearl Walker, "1.142, Stretching of Plastic Shopping Bags", The Flying Circus of Physics Ed. 2, p. 69.


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.