Low
Cost Category
2002 AAPT Apparatus Competition, Boise State University
Name:
Machele Cable
Address: Box 7507 Reynolda Station
Physics
Dept.
Wake
Forest University
Winston-Salem, NC 27052
Phone: 336-758-5532
Fax: 336-758-6142
E-mail: cablem@wfu.edu
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you currently from a High School? no
Name of School:
Apparatus
Title: Lecture Size Pith Balls
Abstract
(40-50 words)
While pith balls are
often used to show electrostatic properties, for a class much larger than a few
students, it can be hard to see them react appreciably. Thus, two Styrofoam cups have been used to
successfully replace the small pith balls used in the past.
Equipment required to construct apparatus:
|
Item |
Source |
Amount |
Cost |
|
Cotton thread |
Walmart |
400 yards |
1.38 |
|
Styrofoam cups |
Walmart |
75/pack |
0.97 |
|
Beads (10 mm) |
Walmart |
60/pack |
0.58 |
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Total Cost |
|
$2.93 for 30 pairs
or |
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Description:
Equipment needed to construct apparatus: String, 2 styrofoam cups, sharp object to punch such as pencil, large plastic beads.
How to make:
- Using the sharp object, carefully punch a small hole in the bottom of the cup.
- Cut an appropriate length of string (50 cm usually is plenty for hanging).
- Thread the string through the hole.
- Tie a bead to the end of the string that will be pulled inside the cup.
- Hang the cup from the other end.
- Repeat for a second cup to create a pair.
Sketch (computer generated if possible):
