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Millikan's mesurement of e

This animation shows Millikan's experiment for the measurement of the charge on the electron (e). Pressing Start releases an oil drop which falls into the gap between the plates. Using the slider you can adjust the potential difference between the plates to bring the drop to rest.

The charge on the drop is then given by the formula: mg = qV/d where d is the separation between the pales.

© Keith Gibbs/John Bourne 2011