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Re: Millikan Apparatus- best one ?



I believe there is some misunderstanding regarding the direction the
experimenter should take in establishing an exact value for e...

There's no misunderstanding. I own a copy of "The Electron" which was
discarded in the 1930s, long before the Dover edition came out. My
point is this: quantization of charge cannot be determined by measuring
five different *charges* on a single drop. It requires that an accurate
determination of the charge be made in order to ensure that charge is
really quantized. To say with confidence that one has 17e on a drop one
must have determined the result to the order of 1%. That is a difficult
feat with oil (but I've done it*). I'm unwilling to believe it is a lot
easier with latex balls. Remember, I'm talking about an uncertainty of
+/-1% for a single measurement (on a droplet which does not change its
charge state during the measurement), not the uncertainty one calculates
from a number of separate measurements.

Leigh

*While that was my uncertainty, my error was larger than that.
There was a systematic error in my measurements, probably due
to an inaccurate voltmeter.