Electroscope is:

An electroscope

This is really a set of three static scenarios. Using the buttons, you can choose between an uncharged electroscope, a positively charged electroscope, and a negatively charged electroscope. Just by looking at a charged electroscope, with the needle away from its uncharged, almost vertical, position, you can't tell the sign of the charge it has. Unlike in this simulation, you can't see the charges!

A negatively charged electroscope has an excess number of electrons. A positively charged electroscope has a deficit of electrons. An uncharged electroscope has plenty of electrons, but the net charge is zero - there are as many protons as electrons. Note that positive charges are shown in red, and negative charges are shown in blue.

Simulation written by Andrew Duffy, and first posted on 12-11-2018.

Creative Commons License
This work by Andrew Duffy is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This simulation can be found in the collection at http://physics.bu.edu/~duffy/classroom.html.

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