(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

We know that, within the limits of measurement, the magnitudes of negative charge on the electron and the positive charge on the proton are equal. Suppose, however, that these magnitudes differed from each other by as little as 0.00010%. With what force would two copper pennies, placed 1.0m apart, then repel each other? What do you conclude? Assume a penny has a mass of 3.11g and is made of copper (atomic weight = 63.5 g/mol, and atomic number = 29)

2. Relevant equations

F = kq^2/r^2 and 1mol = 6.02*10^23

3. The attempt at a solution

There are many given conditions, but it seems some of them are non-use. I absolutely got confused. Shall I find the number of the atomic first? Like 3.11*6.02*10^23/63.5 but what is the difference between this and 29? And how to use 0.00010%? =.= Help Please~

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# Homework Help: Help! The force between copper pennies.

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