may 8, 1868 - Robert Millikan
Millikan is best known for finding the charge of single electron. Thus, he quantified the charge of an electron, which helped later scientists in their research and experiments. His experiments also supported the theory that there indeed were subatomic particles, and disputed people who were opposed to the theory. To find the charge of an electron, Millikan allowed droplets of oil to fall between electrically charged plates called electrodes. The force of the droplets passing through was measured, as was the electrical field between the electrodes. They then used their findings to calculate and identify the charge of an electron.
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