Touching electroscope with charged pipe: Observational Experiment


To observe and explain charging and discharging of the electroscope by contact with charged pipe and hand respectively.

Prior Knowledge

Parts of the electroscope.

Description of the Experiment

A foam pipe rubbed with the rabbit fur has a negative charge. Observe the pipe being rubbed with fur and touching the top of the electroscope. Observe what happens after Alan touches the top of the electroscope.

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  1. Observe the experiment. Draw a picture representing the charges on the pipe and on the electroscope before and after Alan touches it with the pipe.
  2. Explain why the leaf of the electroscope deflects after it was touched with the charged pipe.
  3. Explain why the leaf goes back to the vertical position after Alan touched the electroscope.
  4. What do you need to assume about the structure of the human body in order to explain the observations?
  5. How can you test these assumptions?