A question about Electric Charge

AI Thread Summary
The discussion centers on the concept of electric charge, specifically questioning the implications of a slight difference in charge magnitudes between electrons and protons. Participants agree that Coulomb's law is the relevant equation to calculate the repulsive force between two copper pennies placed 1.2 meters apart, each containing approximately 3 x 10^22 copper atoms. The conversation highlights that if the charges were to differ by 0.00007%, the resulting force would be significant enough to demonstrate that such a difference is implausible. The participants emphasize the need for a deeper understanding of the forces acting on the pennies, particularly the repulsive force. Ultimately, the discussion underscores the importance of consistent charge magnitudes in atomic structure.
Daysi
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We know that the negative charge on the electron and the positive charge on the proton are equal. Suppose, however, that these magnitudes differ from each other by 0.00007%. With what force would two copper pennies, placed 1.2 m apart, repel each other? Assume that each coin contains 3 multiplied by 10^22 copper atoms. (Hint: A neutral copper atom contains 29 protons and 29 electrons.)

(From your answer, it should be obvious that the magnitude of the charge on a proton and the charge on an electron cannot possibly differ by as much as the given percentage.)
 
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Hi Daysi, welcome to PF.
Read the rules of PF. Before you ask for help you have to show you efforts.
What are the relevant equations you can use in the problem?
 
ahh sorry. haven't read the rules yet.
I'm sure we can use Coulomb's law.
F=KQq/r²
 
Your relevant equation is correct.What are the different forces acting on one pennies by the other?
 
Repulsive force and attractive force? and the repulsive one is slightly larger?
 
and q=29e?
I don't know how to do the rest...
 
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