1J40.20 - Torque Beam

Code Number:
Demo Title:
Torque Beam
Center of Mass
Area of Study:
Meter Stick Balance on Vertical Stand, Masses (asst.), and Screwdriver Pivot.

Video Credit: Jonathan M. Sullivan-Wood.

Hang the beam on the screwdriver pivot. The beam has loops every 10 cm.

NOTE: The beam has 5 sections on each side of the pivot.

Then a 1 kilogram mass at 10 cm can be balanced by a 200 g mass at 50 cm on the other side of the pivot.

  • Paul Hewitt, "Answer to September 2019 Figuring Physics", TPT, Vol. 57, #7, Oct. 2019, p. 500.
  • W. Brian Lane, "A New Twist on Torque Labs", TPT, Vol. 52, #9, Dec. 2014, p. 529.
  • Concetto Gianino, "An MBL Experiment to Analyze the Torque on a Rigid Body", TPT, Vol. 47, #4, Apr. 2009, p. 224.
  • Paul Hewitt, "Figuring Physics: Balanced Room", TPT, Vol. 45, #6, Sept. 2007, p. 332.
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  • Paul Hewitt, "Figuring Physics: Golf Balls in Stable Equilibrium", TPT, Vol. 36, #8, Nov. 1998, p. 486.
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  • Morton A. Fineman and Carl Burnett Jr. III, "Another Approach to Solving Problems in Rotational Statics", TPT, Vol. 23, #5, May 1985, p. 299.
  • J. Higbie, "The Level Law from a Symmetry Consideration", TPT, Vol. 18, #5, May 1980, p. 367.
  • Terry Lee Templeton, "Saw-Horse on Teeter-Totter for One Person", TPT, Vol. 5, #3, Mar. 1967, p. 138, also A Potpourri of Physics Teaching Ideas - Mechanics, p. 10.
  • G. D. Freier and F. J. Anderson, "Mo-1", A Demonstration Handbook for Physics.
  • Robert Ehrlich, "F.16. Angular Rotation of a Beam", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 83 - 84.
  • Robert Ehrlich, "D.8. Pennies Balanced on a Ruler", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 48.
  • Jodi and Roy McCullough, "Torque with a Balance Toy", The Role of Toys in Teaching Physics, p. 4.108.
  • Janice VanCleave, "183. Balancing Point", Janice VanCleave's 203 Icy, Freezing, Frosty, Cool, and Wild Experiments.
  • Julius Sumner Miller, Q137 & A137, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 24 & 84.

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