Question

how the oil drop was made stationary in Millikan's experiment?​

Answer 1

In a Millikan's set-up, a charged oil drop falls under gravity with a certain terminal speed. The drop is held stationary applying suitable electric field and is found to carry 2 excess electrons. Suddenly the drop is found to move upwards with the same terminal velocity.

#ANONYMOUS

Answer 2

Millikan's experiment:-

• The force on any electric charge in an electric field is equal to the product of the charge and the electric field.
• Millikan was able to measure both the amount of electric force and magnitude of electric field on the tiny charge of an isolated oil droplet and from the data determine the magnitude of the charge itself.

• In 1909, Robert Millikan and Harvey Fletcher conducted the oil drop experiment to determine the charge of an electron.
• They suspended tiny charged droplets of oil between two metal electrodes by balancing downward gravitational force with upward drag and electric forces.