Puzzle - determine the charge

Determine the value of the charge and set it here
-5 nC +5 nC

In this simulation, the charged particle (in green) is randomly assigned a sign and a magnitude that is either 1, 2, 3, 4, or 5 nC. Your goal is to determine the charge - when you have figured out what it is, set the charge slider to that value and check your answer.
to help you determine the charge, the field vector pattern near the charge is shown.
There is also an electric field sensor (in red) that you can click-and-drag, moving it around the screen to sense both the electric field and the electric potential. The readouts of the position, field, and potential are at the bottom.

Simulation first posted on 3-2-2016. Written by Andrew Duffy

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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