How Would Changes in Coulomb's Law Affect Electrostatic Interactions?

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If Coulomb's law were modified to make electric force independent of distance, a charged comb would not cause a neutral insulator to become polarized, as polarization relies on the varying forces acting on charges at different distances. Consequently, the insulator would not be attracted to the comb. Regarding the two metal spheres, if they touch and are equally charged, they would neutralize and not cling together. However, if they have different charges, touching would allow charge transfer, potentially leading to attraction due to induction. The clarity of the questions posed was noted as a concern in understanding these concepts.
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Homework Statement



1)Coulomb's law states that the electric force becomes weaker with increasing distance. Suppose that instead the electric force between two charged particles were independent of distance. In this case, would a charged comb still cause a neutral insulator to become polarized? why or why not? Would a neutral insulator still be attracted to the comb? why or not why?

2)Two metal spheres are hanging from nylon threads. When you bring the spheres close to each other, you notice that they tend to attract. Is it possible that after the spheres touch, they will cling together? why or why not?

Homework Equations


The Attempt at a Solution


Here are my attempts. Please correct me if I'm wrong and elaborate on why I'm right if I'm right.

1)If the electric forces between two charged particles were independent, would this mean the amount of force will be the same anywhere? If this is the case, the charged comb will cause the neutral insulator to become polarized because there is a electric force acting on it and the insulator will be attracted to the comb.

2)I don't really get how induced charges work. Are the protons and electrons positioning themselves so that the spheres will be polarized? if they touch, wouldn't charges be transferred to each sphere to neutralize them. If this is true, then they can't cling together. I need someone to explain this to me
 
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1) There shouldn't be a force on the insulator. The reason for polarization is because the repulsive force on the like charges, when further away from the comb, is less than the attractive force on the unlike charges closer to the comb. Therefore the insulator becomes polarized. But if the Coulomb's law had no distance factor, the forces would be equal, and there woouldn't be any polarization, and so no attractive force. I hope that's understandable.

2)I don't get it. are the spheres initially charged? If they are, then if they are equally charged, then after touching they would both be neutral and will not attractive. If there is a difference in charge magnitude, then after touching there would be some charge, and induction will cause the spheres to attract. The question isn't very clear.
 
jix said:
1) There shouldn't be a force on the insulator. The reason for polarization is because the repulsive force on the like charges, when further away from the comb, is less than the attractive force on the unlike charges closer to the comb. Therefore the insulator becomes polarized. But if the Coulomb's law had no distance factor, the forces would be equal, and there woouldn't be any polarization, and so no attractive force. I hope that's understandable.

2)I don't get it. are the spheres initially charged? If they are, then if they are equally charged, then after touching they would both be neutral and will not attractive. If there is a difference in charge magnitude, then after touching there would be some charge, and induction will cause the spheres to attract. The question isn't very clear.

thanks. i think you answered both my questions
 
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