Millikan experiment consisted in finding the minimum possible charge by obtaining the tiniest drop possible.
Then, he inferred that was the charge of the electron, given that it was not possible to find a lower charge.
Given these recorded data:
- 6.9 * 10^-19
- 9.2 * 10^-19
- 11.5 * 10^-19
- 4.6 * 10^-19
You must find a number that divide the four data and yields a whole number.
This number is -2.3 * 10^ -19.
In that way you find:
- 6.9 * 10^-19 / -2.3 * 10 ^ -19 = 3 => 3 electrons
- 9.2 * 10^-19 / -2.3 * 10^-19 = 4 => 4 electrons
- 11.5 * 10^-19 / -2.3 * 10^ -19 = 5 => 5 electrons
- 4.6 * 10^-19 / -2.3 * 10^ -19 = 2 => 2 electrons
And you can conclude that the charge of the electron is -2.3 * 10 ^ -19
Answer: -2.3 * 10^ -19
