Can (v1-v2) Prove the Existence of the Smallest Unit of Electric Charge?

AI Thread Summary
The discussion revolves around analyzing the oil drop experiment to explore the existence of the smallest unit of electric charge. The relationship between the velocities v1 and v2, influenced by gravitational and electric forces, is established, leading to the conclusion that (v1 - v2) is proportional to 2FQ. This suggests that repeated trials can reveal a consistent charge Q, which may be an integral multiple of a smaller charge, potentially the charge of an electron. The challenge lies in accurately determining the mass of each droplet, as fluctuations in (v1 - v2) were noted during experimentation. Overall, the experiment is recognized as a clever method for investigating fundamental electric charge properties.
Inquiring_Mike
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We recently did a lab where we were given an animation of the oil drop experiment, and we were supposed to find the velocity of the droplet when Fg and FQ were in the same direction (v1) and when Fg and FQ were in opposite directions (v2)... Then we found (v1 - v2) and were told to analyze and prove the existence of a smallest unit of electric charge...
Here is the work I've done so far...

v1 (is directly proportional to) Fg + FQ
v2 (is directly proportional to) Fg - FQ

Therefore,
(v1 - v2) (is directly proportional to) (Fg + FQ) - (Fg - FQ)
(v1 - v2) (is directly proportional to) Fg -Fg + 2FQ
(v1 - v2) (is directly proportional to) 2FQ

Am I completely off track, can the fact that (v1-v2) is directly proportional to 2FQ be used to prove the existence of the smallest unit of electric charge?
 
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The definate answer is ... maybe.

You need to do this many times. Each time, the charge, Q, will be different. If you accurately determine Q, you will eventually see that it is always an integral number times a smaller charge, q. If you are lucky, that smaller charge q=e (the charge on an electron). If you are not lucky, it might equal 2e, or 3e. As you do more trials, the chance of being unlucky becomes vanishingly small.

I always thought this was one of the cleverest experiments ever.

Njorl

edited to add- the nasty part is to determine the mass of each droplet.
 
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When I did the experiment, I found that (v1 - v2) was constant... Well pretty much, it fluctuated a little bit...
 
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