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Millikan Oil Drop Exploration Documents

Main Document

Millikan Oil Drop Exploration 

written by Slavomir Tuleja, Wolfgang Christian, Mario Belloni, and Anne Cox

The Millikan Oil Drop Exploration is a virtual version of the Millikan's experiment.2 The experiment was based on balancing forces: the gravitational pull down on an oil drop and the electric force up on ionized particles. Below is a schematic of the apparatus. The sprayer releases ionized oil drops into the apparatus. The oil drops fall and enter the a region where they can be seen through the microscope. Turning on the applied voltage provides a force that can, if adjusted correctly, exactly balance the gravitational force on the drop.

The Millikan Oil Drop Java applet was written by Slavo Tuleja.  It was converted from Java to JavaScript by W. Christian using the SwingJS system developed at St. Olaf College.

Last Modified November 25, 2019

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