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Free Fall 3D Model Applet Page

Free Fall 3D Applet

The Free Fall 3D simulates a ball falling with constant acceleration g=-9.8 m/s2 in the z direction. Click-dragging on the ball changes its height but leaves its velocity unchanged. The reset button stops the animation and sets the initial conditions to y=1.8 and vy=0. See the Free Fall model for a description of this model is implemented in Ejs.


The model's 3D view has many built in features that can be accessed as the program is running by right and left clicking within the applet.

  • Left-button click-dragging on the particle changes its position.
  • Left-button click-dragging on an empty regions rotates the view.
  • Left-button shift-click-dragging zooms in and out.
  • Left-button control-click-dragging translates (pans) the view.


The Free Fall 3D Model was created by Wolfgang Christian using the Easy Java Simulations (EJS) version 4.1 authoring and modeling tool to demonstrate how to create a 3D view. The Free Fall 3D archive is located in the OSP Collection within the comPADRE National Science Digital Library.

Information about EJS is available at http://www.um.es/fem/Ejs/.
Additional information on this applet can be found in the Open Source Physics comPADRE collection.
OSP Projects:
Open Source Physics - EJS Modeling
Physlet Physics
Physlet Quantum Physics
STP Book