Robert Millikan (1868-1953)

Millikan was a United States physicist. He won the Nobel Prize for physics in 1923 for being the first scientist to measure the charge of an electron.
He did an experiment, known as the oil drop experiment, in which he was able to measure the amount of an electric force,
and the size of an electric field acting on a charged droplet of oil.
From this he calculated the size of the charge carried by an electron.
During the 1920s Millikan researched into cosmic rays and showed that they come from space.

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