5A30.10 - Electroscope - Wire vs. String

Set the electroscope so that it has a string and copper wire connected to it.  Connect the other end of the string to one of the plastic supports and set to one side of the electroscope.  The copper wire can be connected to the plastic support on the other side of the electroscope.  When the charged PVC rod is brought near the string there is no change observed on the electroscope.  Bringing the charged rod to the copper wire will show a instantaneous response on the electroscope.
Code Number:
5A30.10
Demo Title:
Electroscope - Wire vs. String
Condition:
Good
Principle:
Electrostatic Deflection & Detection
Area of Study:
Electricity & Magnetism
Equipment:
String, uninsulated copper wire, electroscope, PVC charging rod, cats fur, plastic support.
Procedure:

Set the electroscope so that it has a string and copper wire connected to it.  Connect the other end of the string to one of the plastic supports and set to one side of the electroscope.  The copper wire can be connected to the plastic support on the other side of the electroscope.  When the charged PVC rod is brought near the string there is no change observed on the electroscope.  Bringing the charged rod to the copper wire will show a instantaneous response on the electroscope.

References:
  • Xueli Zou, "Conductors and Insulators: A QuickTime Movie", TPT, Vol. 43, # 7, p. 460.

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