Is there a reference that shows the temporal evolution of the electron's charge values? The most I've found is a statement that the values did change, but not what those values were. And so they eliminated the numbers that were too far off, and did other things like that. When they got a number close to Millikan's value they didn't look so hard. Why didn't they discover the new number was higher right away? It's a thing that scientists are ashamed of-this history-because it's apparent that people did things like this: When they got a number that was too high above Millikan's, they thought something must be wrong-and they would look for and find a reason why something might be wrong. If you plot them as a function of time, you find that one is a little bit bigger than Millikan's, and the next one's a little bit bigger than that, and the next one's a little bit bigger than that, until finally they settle down to a number which is higher. Extra Credit Measure the area over which the new copper was deposited, and (using a vernier caliper) the thickness of. Calculate the percent difference between the value and the currently accepted value of 1.6 x 10(-19) Coulombs. Me 9.10938356 10-31 kilos is the value of electron mass of electron. It's interesting to look at the history of measurements of the charge of an electron, after Millikan. Use this result in Equation 2b and solve for the electronic charge e. An electron has a mass of electron of 1/1836 that of a proton. Richard Feynman is quoted as saying, in 1974, that subsequent experimental attempts to measure the charge were biased by Millikan's initial value: Most of the volume of an atom is occupied by electrons, even. Electrons are bound to the nucleus by electrostatic forces.

In all neutral atoms there are the same number of electrons as protons. The mass of an electron is known to be 9.10939 × 10 31 kilograms. Where can I find a paper or reference that describes the timeline of measurements of the magnitude of the electron's electric charge.įor context, Millikan's oil drop experiment in 1908 determined the charge of the electron to be 1.59*10^(-19) C, which is lower than today's accepted value. Recent studies show that the charge of an electron is 1.60218 × 10 19 coulombs.

Charge of electron