About

Coulomb Pendulum Model

Two charges hanging from wires, repel each other. The simulation shows the motion and reports angle (from the vertical) for each charge. You can change the charge (in μC), initial position and damp the motion (set velocity equal to zero) of the charges. Users can examine the model if Ejs is installed. 

Exercises:

1. For the same initial charge on each, push the v=0 button until the charges balance. What is the angle?
2. If you increase the value of one charge, what difference do you expect in the angles where they will balance? Will it still be symmetric? Explain and then try it. 
3. The charge is given in μC and the support string for each is 1m in length. Determine the mass of each (they have the same mass). 

References:

• Giancoli, Physics for Scientists and Engineers, 4th edition, Chapter 21 (2008).

Credits:

The Coulomb Pendulum Model was created by Anne Cox and converted to JavaScript by Fremont Teng and Loo Kan Wee using the Easy Java Simulations (EJS) authoring and modeling tool.

You can examine and modify a compiled EJS model if you run the program by double clicking on the model's jar file.  Right-click within the running program and select "Open EJS Model" from the pop-up menu to copy the model's XML description into EJS.  You must, of course, have EJS installed on your computer. 

Information about EJS is available at: <http://www.um.es/fem/Ejs/> and in the OSP ComPADRE collection <http://www.compadre.org/OSP/>.

 

Translations

Code	Language		Translator	Run

Credits

Anne J Cox; Fremont Teng; Loo Kang Wee

Sample Learning Goals

[text]

For Teachers

Coulomb Pendulum JavaScript Simulation Applet HTML5

Instructions

Charge Field Box and Slider

Zero Velocity Button

Draggable Boxes

Toggling Full Screen

Play/Pause, Step and Reset Buttons

Research

[text]

Video

1. https://www.youtube.com/watch?v=Lu_ejsOeD-U by ETDtogo 
2. https://www.youtube.com/watch?v=N6rgTYMy9Cw by ETDtogo 
3. https://www.youtube.com/watch?v=LlPRzY6EvVI  by ETDtogo 

 Version:

Other Resources

[text]

end faq

{accordionfaq faqid=accordion4 faqclass="lightnessfaq defaulticon headerbackground headerborder contentbackground contentborder round5"}