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.

 Choose a Topic or Enter a keyword to search: I cannot find what I want! You have selected the following Demos: None Selected

Choose a subtopic:
Measurement
Motion In One Dimension
Motion In Two Dimensions
Newton's First Law
Newton's Second Law
Newton's Third Law
Statics Of Rigid Bodies
video  - Center of Mass of Virginia
video  - Center of Mass Toys
Stacking Blocks
video  - Stability Track
photos  - Tension in a String
Rope and Three Students
photos  - Knot in Static Equilibrium
Force and Tension
The Roman Arch
Rotational Equilibrium
video  - Giant Yo-Yo
Applications Of Newton's Laws
Gravity
Work and Energy
Momentum
Rotational Motion
Properties of Matter

### Rotational Equilibrium

#### Purpose:

To show that the sum of the torques is zero when a body is in rotational equilibrium.

#### Procedure:

1. Mount plate by inserting support rod. Tie strings to holes on rim of plate. Position strings over pulleys and hang weights on ends. Calculate torques and verify that in equilibrium the sum of the torques is zero.
2. Measure angles of forces using plumb bob as a vertical reference. By setting sum of horizontal and vertical components equal to zero, show that force exerted by axis is zero. Remove axis.

#### Equipment:

• Meter Stick
• Irregular Plate
• Large Protractor
• Plumb Bob
• Pulley
• Stand
• String
• Support w/ rod to fit in center hole
• Weights