Robert Millikan

Blurbs

About me:

I died but I'm back from the dead LOL! Back in '09 (1909) me and my homie Harvey Fletcher performed the oil drop experiment while I was a professor at the U of Chicago.

Through the oil drop experiment, I was able to calculate the charge of an electron. I devised a chamber with two horizontal, parallel charged metal plates. The top plate had a small hole. An atomizer sprayed droplets of oil into the chamber, and I could watch them fall through a microscope on the side of the chamber.

I initially sprayed the oil drops while the plates were not charged, and they fell through the hole, electrifying because of friction. When I did turn them on, I could manipulate the drops upwards or downwards or cause them to hover by changing the potential difference of the plates. By measuring the drops’ velocity, mass, and voltage, I was able to calculate the charge of each droplet. Finding that the charges were always multiples of a value of 1.5924 × 10−19 coulombs, I determined that that was the charge of a single electron .