What happens to the Electrical Potential the closer we are to a point charge?

In summary, the potential for a point charge at the origin, as described by V=1/(4πε) * q/r with the reference point at infinity, goes towards infinity as the distance between two charges decreases. This is due to the limitations of Coulomb's law, which only applies to point particles and cannot account for the sizes of the objects or other physics that may come into play at smaller distances.
  • #1
SebastianRM
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So I have been wondering:
The potential for a point charge at the origin, is described as:
(Using the reference point at infinity): V=1/(4πε) * q/r
My question is, what happens to this Potential the closer we are to the point charge, and so the closer we would get, the Potential seems to go towards infinity, which does not make sense, so I would like to understand how to approach the idea since my approach gives me an illogical answer.
 
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  • #2
Yes, it does go toward infinity, as you suspected. So what does this mean for another charge as it approaches the one at the origin?
 
  • #3
Its potential would be stronger the closer this one is to it? And how can a Potential go towards infinity, I feel pretty lost on the subject. Thank you for the help btw!
 
  • #4
So let's agree that you cannot put zero in the denominator. Physically, the distance between two charges will always be some tiny amount.
If the charge at the origin is positive, bringing another positive charge close to it will become increasingly difficult, as you get closer. Maybe this site will help you. http://hyperphysics.phy-astr.gsu.edu/hbase/electric/potpoi.html
 
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  • #5
SebastianRM said:
the Potential seems to go towards infinity, which does not make sense,
Indeed it does not. This is the math telling you that ##F=CQ_1Q_2/r^2## for point particles only works when ##r\ne{0}##.

If f you try to bring two charged objects together to drive the potential and the force between them to infinity, some other physics that you've been ignoring for larger values of ##r## will start to matter and Coulomb's law is no longer the whole story. For example, if the objects have non-zero sizes ##R_1## and ##R_2##, you can't reduce the distance between them to less than ##R_1+R_2## so plugging a smaller value into Coulomb's law makes no sense.
 
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1. What is electrical potential?

Electrical potential is the amount of electric potential energy that a charged particle has at a specific point in an electric field.

2. How does distance affect the electrical potential near a point charge?

The electrical potential near a point charge decreases as the distance from the charge increases. This is because the electric field strength decreases with distance, resulting in a lower potential energy for the charged particle.

3. What is the relationship between distance and electrical potential near a point charge?

As distance increases, the electrical potential near a point charge decreases. This relationship is inversely proportional, meaning that as one value increases, the other decreases.

4. Can the electrical potential near a point charge ever be zero?

Yes, the electrical potential near a point charge can be zero if the charged particle is located at infinity. This is because at infinity, the distance from the point charge is infinitely large, resulting in a potential energy of zero.

5. How does the charge of the point charge affect the electrical potential near it?

The charge of the point charge directly affects the electrical potential near it. As the charge of the point charge increases, the electrical potential also increases. This is because a larger charge will create a stronger electric field, resulting in a higher potential energy for charged particles near it.

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