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B Why is electric potential present inside a conductor?

  1. Jun 1, 2017 #1
    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 isnt any force to act against why would electric potential be present over there?
     
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  3. Jun 1, 2017 #2

    Drakkith

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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?
     
  4. Jun 1, 2017 #3
    so this means the work which was done on a positive charge to bring it doesnt increase when the charge is taken inside the conductor. hence potential also doesnt increase. therefore the potential isnt zero but same as on the surface of the conductor
     
  5. Jun 1, 2017 #4

    Drakkith

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    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?
     
  6. Jun 1, 2017 #5
    sorry for making it vague.can u please tell me if i m wrong anywhere in my thought process? lets 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 doesnt 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 doesnt change once the charge is inside the conductor so the potential doesnt change. therefore its constant.
     
  7. Jun 1, 2017 #6

    Drakkith

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    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!
     
  8. Jun 1, 2017 #7
    Your thought process is absolutely right.
     
  9. Jun 1, 2017 #8
    thanks for ur help
     
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