Why is electric potential present inside a conductor?

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Discussion Overview

The discussion revolves around the concept of electric potential inside a conductor, particularly focusing on the behavior of electric potential and electric fields in relation to charges placed inside and outside a conductor. The scope includes theoretical reasoning and conceptual clarification regarding electrostatics.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant describes potential energy as the work done by an external force in moving a charge, questioning why electric potential exists inside a conductor where the net electric field is zero.
  • Another participant argues that when a positive charge is placed inside a hollow conductor, the charges rearrange to cancel the field inside, but a field must still exist outside the conductor.
  • A different viewpoint suggests that the work done on a positive charge does not increase when it is moved inside the conductor, implying that the potential remains the same as on the surface of the conductor.
  • One participant requests clarification on the setup of the thought experiment to ensure a clear understanding of the situation being discussed.
  • A participant reiterates their reasoning about the electric potential, explaining that as a test charge approaches the conductor, its potential energy increases until it reaches the surface, and then remains constant once inside.
  • Another participant expresses uncertainty about the question and hopes for further input from others.
  • A later reply confirms the reasoning of the previous participant, stating that their thought process is correct.

Areas of Agreement / Disagreement

Participants express differing views on the nature of electric potential inside a conductor, with some agreeing on the reasoning presented while others raise questions and seek clarification. The discussion remains unresolved regarding the implications of electric potential and fields within and outside the conductor.

Contextual Notes

Some assumptions about the setup of the thought experiment are not fully defined, and there are unresolved aspects regarding the relationship between electric potential and electric fields in this context.

esha
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potential energy is the work done by an external force in taking a body from a point to another against a force. on the surface of a conductor the electrostatic charges arrange themselves in such a way that the net electric field is always zero. so if there isn't any force to act against why would electric potential be present over there?
 
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Consider a positive charge placed inside a hollow conductor. The charges inside the conductor arrange themselves such that they cancel out the field inside the conductor, but outside of the sphere the field must still exist, otherwise you'd have a positive charge whose field just ends inside a neutral object. Does that make sense?
 
so this means the work which was done on a positive charge to bring it doesn't increase when the charge is taken inside the conductor. hence potential also doesn't increase. therefore the potential isn't zero but same as on the surface of the conductor
 
Sorry, but I think it would help to clarify the exact setup of our little thought experiment prior to moving anything. That way we know exactly what we are dealing with. Do you have a particular example in mind?
 
sorry for making it vague.can u please tell me if i m wrong anywhere in my thought process? let's consider a conductor which has charges distributed on it. now due to these charges there is an electric field present on the exterior part of the conductor. let there be another test charge which is progressing towards it. as its progressing its potential energy difference is increasing. the reason being the force against which its moving is also increasing. when its on the surface of the conductor it becomes maximum. the moment it enters the conductor it doesn't increase neither decrease. we know that electric potential is the diffrence of potential energy between two points divided by the charge. in my case consider that one point is on infinity and the other is inside the conductor. we can clearly see that the difference doesn't change once the charge is inside the conductor so the potential doesn't change. therefore its constant.
 
Hmm. That's a good question and it's one that I don't think I can answer. Hopefully someone else will be able to. Sorry!
 
esha said:
sorry for making it vague.can u please tell me if i m wrong anywhere in my thought process? let's consider a conductor which has charges distributed on it. now due to these charges there is an electric field present on the exterior part of the conductor. let there be another test charge which is progressing towards it. as its progressing its potential energy difference is increasing. the reason being the force against which its moving is also increasing. when its on the surface of the conductor it becomes maximum. the moment it enters the conductor it doesn't increase neither decrease. we know that electric potential is the diffrence of potential energy between two points divided by the charge. in my case consider that one point is on infinity and the other is inside the conductor. we can clearly see that the difference doesn't change once the charge is inside the conductor so the potential doesn't change. therefore its constant.

Your thought process is absolutely right.
 
thanks for ur help
 

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