nov 19, 1909 - Oil Drop Experiment

Description:

It measured both the amount of electric force and magnitude of electric field on the tiny charge of an oil droplet, and from the data determine the magnitude of the charge of an electron. This showed that electrons have a negative charge. Robert Milikan is directly related to this event, as he conducted the experiment.
(Image: https://cdn.britannica.com/82/22482-050-40927428/oil-drop-experiment-Millikan-series-multiples-experiments-American-1910.jpg)

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