In 1910 Robert Millikan succeeded in precisely determining the magnitude of the electron's charge. Small electrically charged drops of oil were suspended between two metal plates where they were subjected to the downward force of gravity and the upward attraction of an electrical field.

What did Millikan discover about atoms?

Millikan discovered that there is a fundamental electric charge—the charge of an electron. Rutherford's gold foil experiment showed that atoms have a small, dense, positively charged nucleus; the positively charged particles within the nucleus are called protons.

What did Mr Millikan discover?

Robert Millikan was a physicist who discovered the elementary charge of an electron using the oil-drop experiment.