Charging by conduction with and odd net charge?

AI Thread Summary
When two conducting spheres, A (neutral) and B (charged -3e), touch, charge redistribution occurs, but they cannot have fractional charges. The total charge of the system is conserved, so the charge will distribute in a way that maintains the overall charge balance. The movement of electrons during contact is influenced by thermal randomness, meaning that one electron may transfer to the neutral sphere, but it is uncertain how many will move. Typically, it is suggested that two electrons may stay on the charged sphere while one moves to the neutral one. This process highlights the principles of charge conservation and electron mobility in conductive materials.
Legaldose
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Hello, I've just got a quick question about charging an object by conduction. I've been studying for my final and I came across a problem that I can't really see how to solve.

Say you have two conducting spheres, A and B. They are both exactly the same in every way except for their electric charge. Say A is electrically neutral and B has a charge of -3e. Now what happens when they touch? I was under the impression that when they come into contact they would share the charge equally, but you can't have a charge of -(3/2)e. So what happens?

Thanks, and happy physics!
 
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Legaldose said:
Hello, I've just got a quick question about charging an object by conduction. I've been studying for my final and I came across a problem that I can't really see how to solve.

Say you have two conducting spheres, A and B. They are both exactly the same in every way except for their electric charge. Say A is electrically neutral and B has a charge of -3e. Now what happens when they touch? I was under the impression that when they come into contact they would share the charge equally, but you can't have a charge of -(3/2)e. So what happens?

Thanks, and happy physics!

Small numbers like that aren't realistic, but I'm pretty sure it would be random which sphere the one extra electron would end up on. Think thermal randomness...
 
one would think the three electrons were initially equidistant from each other on the one sphere. Touching the spheres together would enable at least one of the electrons to move to the second sphere...so I like the 'random' explanation already provided. But an argument might be made that in most cases, two would remain on the initial sphere.
 
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