A Conceptual Difficulty regarding Potentials

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Avi1995
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Plz help me out with this difficulty. Here is a figure showing two conducting spheres(haven't drawn all EF lines):-
Diagram of a large yellow sphere labeled +Q with arrows radiating outward, beside a smaller orange sphere with points A, B and C; minus signs crowd the left side and plus signs the right side.


Here is the problem, Suppose one of the spheres is charged with a charge +Q, other is neutral
, so charges will get induced as shown in figure. The left portion of orange sphere(neutral one)
is at lower potential than the right portion because it has -ve charge and other is +ve.
Since E=0 inside a conductor, we have:-
dV=-E.dr
so if we move from the point A(on left surface) to B, since E=0 we have,
dV=0
so VA =VB
Now if we move from the point C(on right surface) to B, since E=0 we have,
dV=0
so VB =VC
but Va<Vc??
What is wrong in this reasoning?


Homework Equations


dV=-E.dr
 
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Avi1995 said:
Plz help me out with this difficulty. Here is a figure showing two conducting spheres(haven't drawn all EF lines):-
Diagram of a yellow sphere labelled +Q with arrows radiating outward, and an orange sphere on the right with points A, B and C marked; minus signs on its left side and plus signs on its right side.


Here is the problem, Suppose one of the spheres is charged with a charge +Q, other is neutral
, so charges will get induced as shown in figure. The left portion of orange sphere(neutral one)
is at lower potential than the right portion because it has -ve charge and other is +ve.
Since E=0 inside a conductor, we have:-
dV=-E.dr
so if we move from the point A(on left surface) to B, since E=0 we have,
dV=0
so VA =VB
Now if we move from the point C(on right surface) to B, since E=0 we have,
dV=0
so VB =VC
but Va<Vc??
What is wrong in this reasoning?


Homework Equations


dV=-E.dr
The conclusion in sentence I put in RED above is wrong.