Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538
Physics Demo Manual
Demonstrations are cataloged according to PIRA Bibliography
PLEASE REQUEST DEMOS WELL IN ADVANCE
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.
Choose a subtopic:
(Clicking a green button will add that demo to your list)
- 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
- Properties of Matter
video - Center of Mass Toys
To illustrate the concept of center of mass.
DEMO VIDEO DOWNLOAD
Various aspects of center of mass can be demonstrated through creative use of the toys (pictured below).
- Balancing Spoon & Fork with Match Stick: can be used with a cup
- Tiltable Prism: with plumb bob falling within area of its base, the prism stands; if not, the prism falls
- Tightrope Mickey Mouse: with long downward bending pole with masses on either end lowers Mickey's center of mass to below the rope establishing a stable equilibrium in addition to increasing his moment of inertia
- Double Cone rolling up the incline: seems to roll uphill, but actually rolls toward diverging rails
- Balancing Horse: with the center of mass below its feet
- Leaning Tower of Pisa: is unstable with top in place and stable with top removed
- Semi Circle with adjustable ball mass: system stable with ball at bottom of support rod
- Balancing Bird: with the center of mass at the tip of its beak
Try balancing a soda can at 45-deg angle that is full, partially full and empty. You'll find that a stable equilibrium is achieved with a can about 1/3 full.