Millikan Oil Drop Experiment: Determining Elementary Charge

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Sandro Romualdez

Homework Statement



Calculate the charge on each oil drop and determine the elementary charge on an electron given the following:
Voltage (Attached)
d (Distance between two charged plates) = 0.10m
m (Of the droplet) = 1.57x10^-15 kg
g = 9.8 kgm/s^2

Homework Equations


q = mg*d / ΔV

The Attempt at a Solution


I'm just confused on how I should first tackle the problem.

Should I just calculate the ΔV between each voltage, and use that in the equation to calculate the charge between each test/zap (The charge on each drop?), and then get the average charge of all using the mean formula? (Sum of q's/20)

Thanks for any help.
 

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What would the average do for you? Say you had two calculations one of which gave 3.2×10-19 C and the other 4.8×10-19 C. The average is 4×10-19 C. Would you say that's the charge of the electron? Note that I chose the numbers so that the first drop had two extra electrons and the second drop 3 electrons. You need to think some more about this and what you should be doing.
 
Best I can do for you is suggest you wind up with a list of numbers from which you have to find the highest common factor. Note that the data tends to group suggesting only a few actual ΔV, with only slight differences between ΔV of the same group. Those differences you might want to average for each group.

Anything more would be giving too much away.