Torsion Pendulum
Torsion Pendulum demo

 

Code Number: 3A10.30

Demo Title: Torsion Pendulum

Condition: Excellent

Principle: Potential to Kinetic Energy, Simple Harmonic Motion

Area of Study: Oscillations & Acoustics

Equipment: 

Torsion Pendulum.

Procedure:

Stretch the pendulum so that the wire is very tight.  The different mass balls may be used to vary the pendulum period.

The old style torsion pendulum is originally a wall mount type apparatus.  Copper, Brass, and Steel Rods of different diameters and with a nominal length of 1 meter are used with this apparatus.  The rods are stored in the "Mechanics" section.   Note that there is a ring that can also be used with the pendulum that will effectively double the mass. 

References:

  • Andreas Kaps, Tobias Splith, Frank Stallmach, "Shear Modulus Determination Using the Smartphone in a Torsion Pendulum", TPT, Vol. 59, #4, April 2021, p. 268.
  • I. Salinas, M. H. Gimenez, J. A. Monsoriu, and J. A. Sans, "Demonstration of the Parallel Axis Theorem Through a Smartphone", TPT, Vol. 57, #5, May 2019, p. 330.
  • Tribhuvan N. Soorya, "A Modification to Maxwell's Needle Apparatus", TPT, Vol. 53, #5, May 2015, p. 282.
  • "Correction to 'Effective Torsion and Spring Constants in a Hybrid Translational-Rotational Oscillator' Phys. Teach. 49, 106–109 (Feb. 2011)", TPT, Vol. 49, #7, Oct. 2011, p. 405.
  • Zein Nakhoda and Ken Taylor, "Effective Torsion and Spring Constants in a Hybrid Translational-Rotational Oscillator", TPT, Vol. 49, #2, Feb. 2011, p. 106. 
  • Thomas B. Greenslade Jr., "Apparatus Named After Our Academic Ancestors-I", TPT, Vol. 48, #9, Dec. 2010, p. 604.
  • James O'Connell, "Magnetic Torsion Pendulum", TPT, Vol. 38, #6, Sept. 2000, p. 377.
  • Hilton Abbott, "Torsion Resonance Demonstrator", TPT, Vol. 21, #5, May 1983, p. 333.
  • Richard E. Berg and Todd S. Marshall, "Wilberforce Pendulum Oscillations and Normal Modes", AJP, Vol. Vol. 59, #1, Jan. 1991, p. 32.
  • H. M. Simpson and B. E. Fortner, "The Dynamic Shear Modulus and Internal Friction of a Fiber Vibrating in the Torsional Mode", AJP, Vol. 55, #1, Jan. 1987, p. 44.
  • Philip F. Schewe, "Newton's Second Law of Motion", Physics Today, Vol. 60, #6, June 2007, p. 28.
  • "M-904: Pendula - Torsion & Physical", DICK and RAE Demo Notebook.
  • Freier and Anderson, "Mz-1, 2", A Demonstration Handbook For Physics.
  • Richard Manliffe Sutton, "M-167", Demonstration Experiments in Physics.
  • George M. Hopkins, "Cycloid Curve", Experimental Science, p. 52.
  • R. W. Pohl, "4. Moments of Inertia: Torsional Vibrations", Physical Principles of Mechanics and Acoustics, p. 102.
  • Colson, Lapp, and Elridge, Physics Laboratory Manual, University of Iowa, 1936, p. 32.

Video Credit: Jonathan M. Sullivan-Wood.

3A10.30 - SHM - Torsion Pendulum