written by Andrew Duffy

The Three Point Charges is an inquiry-based model for exploring the force between charged objects. Initially, the simulation sets up three charged objects, one at each corner of an equilateral triangle. The charges have different magnitudes, represented by force vectors. The charges can be moved, allowing users to test the electric force in a variety of alignments. The student's task is to rank the charges based on their magnitudes, from largest to smallest. After practicing, students then write and share their methods for determining the correct ranking.

See Supplemental Document below for a student worksheet developed specifically to accompany this simulation.  

See Annotations (below) for an interactive student tutorial on Coulomb's Law, which provides additional content support on electric force.

This item was created with Easy Java Simulations (EJS), a modeling tool that allows users without formal programming experience to generate computer models and simulations. To run the simulation, simply click the Java Archive file below. To modify or customize the model, See Related Materials for detailed instructions on installing and running the EJS Modeling and Authoring Tool.

• Download ejs_bu_em_Three_Point_Charges.jar - 1180kb Java Archive File

Last Modified June 12, 2014

This file has previous versions.

Student worksheet for Three Point Charges Model.

• Download Three_Charges_Worksheet.pdf - 8kb Adobe PDF Document

Last Modified April 16, 2010

This file is included in the full-text index.

The source code zip archive contains an XML representation of the Three Point Charges model.   Unzip this archive in your EJS workspace to compile and run this model using EJS.

• Download ejs_bu_Three_Point_Charges.zip - 7kb Compressed File

Last Modified June 12, 2014

This file has previous versions.