Solving Oil Drop Experiment: Calculate Largest e Value

AI Thread Summary
The discussion revolves around determining the largest fundamental unit of charge (e) consistent with given measurements from an oil drop experiment. Participants clarify that the goal is to find the highest common factor among the provided charge values, which are expressed as fractions. The confusion arises regarding the calculation of ratios and the relevance of averages, with a focus on identifying multiples of the unit. Ultimately, the consensus is that the largest unit consistent with the measurements is 3. Understanding the concept of common factors is crucial for solving the problem effectively.
cake_is_a_lie
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Homework Statement


The values for the charges on oil drops are 3,99 6,65 2,66 10,64 3,99 and 9,31
all these multiplied with x10-19C.
What is the largest value of the fundamental unit of charge that is consistent with the measured charges?


Homework Equations


Fundamental unit of charge is e=1,60x10-19C


The Attempt at a Solution


The question confuses me a little bit. Taking mean average is useless because the highest value is asked. I don't find also any reason to calculate ratios between the measured values althought 6,65/3,99=1,6666...
Any ideas?
 
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hi cake_is_a_lie! :smile:
cake_is_a_lie said:
The values for the charges on oil drops are 3,99 6,65 2,66 10,64 3,99 and 9,31 …

well, they're (approximately) 12/3, 20/3, 8/3, 32/3, and 28/3 … :wink:
 
Thank you for answering.
But I don't really understand the point. Actually this time the explanation and deduction is more useful than the actual answer.
 
well, what's the largest unit consistent with 12/3, 20/3, 8/3, 32/3, and 28/3, being multiples of that unit? :smile:
 
tiny-tim said:
well, what's the largest unit consistent with 12/3, 20/3, 8/3, 32/3, and 28/3, being multiples of that unit? :smile:
cake_is_a_lie said:
If I understand right it is 3. What I meant before was that how did you deduced these common fraction.

nooo :redface: … each value has to be a multiple of the unit

how can 20/3 be a multiple of 3?

you need to find the highest common factor (the highest number which goes into each value a whole number of times) :smile:
 
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