An easy electrodynamics question, and yet

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The discussion revolves around a physics homework problem involving two identical conducting spheres with charges of 12.0 nC and 16.0 nC, placed 0.350 meters apart. The user incorrectly calculated the electric force between the spheres using Coulomb's Law, arriving at 0.000014 N. The error stemmed from misunderstanding the concept of equilibrium and significant digits in the calculation. After connecting the spheres with a conducting wire, the charges redistribute, leading to an average charge of 14.0 nC on each sphere, which must be considered for accurate force calculation.

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My first homework assignment for griffiths is underway.
Here is a problem I can't figure out.

Q. Two identical conducting small spheres are placed with their centers
0.350 meters apart. One is given a charge of 12.0 nC and the other
is given a charge of 16.0 nC The spheres are connected by a
conducting wire. Find the electric force between the two after
equilibrium has occurred.

A. I used Coulombs Law to arrive at .000014 N. This is incorrect. My reasoning was that the conducting wire would allow electrons to redistribute themselves giving the two spheres the same charge which is the average of the two initial charges. I must not understand the concept of equilibrium correctly. I would ask the instructor but the faculty at my institution is on strike presently!

Any suggestions?
 
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Well, even given your assumption (which feels right to me), I don't get the same answer as you do - I'm different by some exponent of 10. Are you certain about your answer?

Also, I think there should be 3 significant digits in your answer.
 
You were right in that it was a problem with the number of significant digits used. The homework is submitted online and the site used is a bit touchy.
Thanks
 

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