1R30.40 - Horizontal Torsion Apparatus - Rod

See procedure.
See procedure.
Code Number:
Demo Title:
Horizontal Torsion Apparatus - Rod
Torsional Rigidity of Rods.
Area of Study:
Torsion Rods, Torsion Apparatus, Table Clamp Socket. Mass Set.

Set the apparatus up as shown making sure that the angular scale is in a place that is easy to read.  You are able to rotate the Vernier scale so that it can be placed at the zero mark.   Hang masses from the strap and note the angular displacement of the twisting rod.  Torque applied should be directly proportional to the angle of twist within the elastic limits of the rod.  Rods of different materials and diameters are available. 

  • S. Tyagi and A. E. Lord, Jr., "An Inexpensive Torsional Pendulum Apparatus for Rigidity Modulus Measurement", AJP, Vol. 47, #7, July 1979, p. 632.
  • Bernard Scott, "Inexpensive Measurements of the Elastic Constants of Steel", AJP, Vol. 45, #1, Jan. 1977, p. 45.
  • D. Colson, C. J. Lapp, J. A. Eldridge, "Experiment XVI", 1936 Univ. of Iowa Physics Laboratory Manual, p. 31.

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