Part 1: Measuring Electric Fields and Equipotentials

Measuring Electric Fields and Equipotentials for Charges

 

We are going to investigate electric fields, both their magnitude and their direction for various charge distributions. In the process we can roughly determine the equipotential surfaces.Begin by looking at the simulation below called monopole.   Start Positive Charge

Make a prediction for what you think the electric field lines will look like surrounding a negative charge. Remember |E|=|F|/q.  

Place all 30 electric field direction indicators (arrows) around the charge. Sketch your results. Also sketch the equipotential surfaces (they are perpendicular to the field lines. Place a magnitude detector in the sim and roughly state the dependence of the electric field strength on the position. 

Also, pick 3 places (corners work well) and write down the magnitude there. Also sketch the equipotential surfaces (they are perpendicular to the field lines. Place a magnitude detector in the sim and roughly state the dependence of the electric field strength on the position. Also, pick 3 places (corners work well) and write down the magnitude there. 

Make a guess as to how the electric field lines will behave if the sign of the charge was changed to negative. Sketch

 

Change the sign of the charge to negative. Start Negative Charge

Now, sketch the electric field lines and equipotential surfaces.

How do the two configurations differ?

Once you sketch your predictions, start the Physlet and see if you were right.