Physics at the University of Virginia
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Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538

Physics Demo Manual

Demonstrations are cataloged according to PIRA Bibliography


Due to Physics Building renovations, the lead time to set up demo requests has increased due to the need to transport equipment across campus. Please be kind and let me know well ahead of time what you need.

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 Motion In One Dimension
 Motion In Two Dimensions
 Newton's First Law
 Newton's Second Law
 Newton's Third Law
 Statics Of Rigid Bodies
 Applications Of Newton's Laws
 Work and Energy
 Rotational Motion
 Rotational Inertia Rods
  video  - Rolling Objects and Moments of Inertia
  video  - Moment of Inertia Wheel
  video  - The Falling Rigid Body
  video  - Vector Nature of Angular Momentum
 Hero's engine
  video  - Precession of Bicycle Wheel Under Gravity Force
 Suitcase Gyro
 Air Gyro
 Euler's Disk
 Tippe Top
 Properties of Matter

Rotational Inertia Rods


To Illustrate the dependence of an objects rotational inertia on its mass distribution.


Bring two students down to the front and give each of them a rod. Let them feel each rod to convince the class that each has the same mass. Have each student hold their rod in the center and try to twist it back and forth as quickly as they can. Even though the rods have the same mass, one rod has its mass concentrated equally at the ends. The student with this rod will have a much harder time twisting the rod back and forth.


This demo works best if you get a strong hulking student and a diminutive one and give the strong student the rod with the mass distributed at the ends.