1R20.15 - Young's Modulus

Code Number:
1R20.15
Demo Title:
Young's Modulus
Condition:
Good
Principle:
Stress & Tension
Area of Study:
Mechanics
Equipment:
Young's Modulus Apparatus, optical lever, laser, 10 each - 1k weights.
Procedure:

NOTE: The device is too tall to get into the room when it is sitting on the table.

The apparatus is set so that we are going to measure the stretch of a 1 meter length of wire (1 meter measured without tension).  Once the apparatus is set on the table, mount the optical lever and align the laser so that you get a reflected dot on the screen.  Start adding 1k weights to the hanger at the bottom of the wire.  The dots should progressively move up the screen with the addition of each weight.

References:
  • Austin D. Korff and Alan J. Scott, "World’s Simplest Materials Lab", TPT, Vol. 56, #9, Dec. 2018, p. 614.
  • Robert D. Polak, Adam R. V. Davenport, Andrew Fischer, Jared Rafferty, "Determining Young's modulus by measuring guitar string frequency", TPT, Vol. 56, #2, Feb. 2018, p. 122. 
  • Kenneth A. Pestka II, "Young's Modules of a Marshmallow", TPT, Vol. 46, #3, Mar. 2008, p. 140.
  • Kenneth A. Pestka II, "The Elastic Constant", TPT, Vol. 45, #6, Sept. 2007, p. 327.
  • W. Larry Freeman, and Ronald F. Freda, "A Simple Experiment for Determining the Elastic Constant of a Fine Wire", TPT, Vol. 45, #4, Apr. 2007, p. 224.
  • Adam Niculescu and Russell Shumaker, "Apparatus for Measuring Young's Modulus", TPT, Vol. 41, #6, Sept. 2003, p. 364.
  • A. P. French, "The Suspended Slinky - A Problem in Static Equilibrium", TPT, Vol. 32, #4, Apr. 1994, p. 244.
  • Zheng Bunker, "An Improved Optical Lever", TPT, Vol. 31, #8, Nov. 1993, p. 510.
  • Thomas B. Greenslade, Jr. and Richard Wilcox, "An Inexpensive Young's Modulus Apparatus", TPT, Vol. 31, #2, Feb. 1993, p. 116.
  • James E. Kettler, "Listening for Young's Modulus", TPT, Vol. 29, #8, Nov. 1991, p. 538.
  • James E. Kettler, "An Elasticity Paradox", TPT, Vol. 28, #6, Sept. 1990, p. 416.
  • R.T. Curry, "Turning the Young's' Modulus Experiment Around", TPT, Vol. 21, #2, Feb. 1983, p. 112.
  • A. Kshatriya, "Laser Beam Optical Lever", TPT, Vol. 12, #8, Nov. 1974, p. 501.
  • J. Flores-Maldonado, S. Galindo, and H. Jimenez-Dominguez, "Erratum: 'Consistency of Minimum Time and Length Intervals with Special Relativity' [Am. J. Phys. 55, 1041 (1987)]", AJP, Vol. 56, #9, Sep. 1988, p. 856.
  • J. Flores-Maldonado, S. Galindo, and H. Jimenez-Dominguez, "Note on an Apparatus for Young's Modulus Measurement", AJP, Vol. 55, #7, July 1987, p. 664.
  • Gauri Shanker, V. K. Gupta, B. Saraf, and N. K. Sharma, "Temperature Variation of Modulus of Rigidity and Internal Friction: An Experiment with Torsional Oscillator", AJP, Vol. 53, #12, Dec. 1985, p. 1192.
  • Somdev Tyagi, Arthur E. Lord Jr., "Simple and Inexpensive Apparatus for Young's Modulus Measurement", AJP, Vol. 48, #3, March 1980, p. 205.
  • T. G. Bullen, "Determination of Young's Modulus in the Freshman Laboratory", AJP Vol. 33, #10, Oct. 1965, p. 855.
  • T. Kallard, "Optical Lever", Exploring Laser Light, p. 43.
  • "Young's Modulus of Elasticity: Measurement of Stretch with Optical Lever", Selective Experiments in Physics, CENCO, 1941.
  • "Young's Modulus of Elasticity: Direct Measurement of Stretch with a Micrometer Screw and Level", Selective Experiments in Physics, CENCO, 1941.
  • "Deflection of a Beam - Young's Modulus", Selective Experiments in Physics, CENCO, 1941.
  • W. Bolton, "Stress Analysis Using Resistance Strain Gauges", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 64.
  • W. Bolton, "Rubber at Low Temperatures", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 64.
  • W. Bolton, "The Strength of Glass Fibres", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 62 - 63.
  • W. Bolton, "The Dynamic Young's Modulus of Rubber", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 14 - 15.
  • W. Bolton, "The Elasticity of Copper", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 12 -13.
  • W. Bolton, "Poisson's Ratio", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 10 - 11.
  • W. Bolton, "Strain", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 9.
  • W. Bolton, "Stress", Book I - Properties of Materials, Physics Experiments and Projects, 1968, p. 7 - 8.


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