Where does this come from, and can I check it?

Balanced oil droplets gave a value for the elementary charge. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a science fact?

Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Millikan measured the electron's charge

Balanced oil droplets gave a value for the elementary charge Robert Millikan suspended tiny charged oil droplets between two plates and adjusted the electric field until they stopped falling. Repeated measurements always gave charges that were whole multiples of a single number. His result, about 1.6 times ten to the minus 19 coulombs, has held up with later refinement. It sits in Mondo's science collection, one of 200 facts that each trace back to the reference below.

Where this comes from

NIST

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: physics, experiment, electrons

Millikan measured the electron's charge: the short answers

Where does this come from, and can I check it?: Balanced oil droplets gave a value for the elementary charge. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a science fact?: Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.