Why is (B) Incorrect in This Electrostatics Question?

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SUMMARY

The discussion clarifies why option (B) is incorrect in the context of electrostatics, specifically regarding charge distribution on conductors. Option (B) suggests that charge spreads evenly over the surface of a conductor, which is misleading. Instead, option (E) is correct, stating that the surface of a conductor becomes an equipotential surface, with charge density varying based on the curvature of the surface. This means that charge density is highest where the radius of curvature is smallest, and the electric field inside the conductor remains zero.

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Homework Statement




Which of the following statements about conductors under electrostatic conditions is true?
(A) Positive work is required to move a positive charge over the surface of a conductor.
(B) Charge that is placed on the surface of a conductor always spreads evenly over the surface.
(C) The electric potential inside a conductor is always zero.
(D) The electric field at the surface of a conductor is tangent to the surface.
(E) The surface of a conductor is always an equipotential surface.

The Attempt at a Solution



I picked (B), but apparently the answer is (E)

Anyone have a clue... why (B) is incorrect?
 
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option E is correct.
 


JhonMoney said:
option E is correct.

Yeah...because I told you.
 


Check your textbook. It gives some examples. Charge is densest where the radius of curvature is smallest and positive. In places where the surface is concave (radius of curvature is negative) there will be practically no excess charge. The charge is distributed so as to make the surface be an equipotential surface. (I know that's the given answer.) but since the E field everywhere in the conductor is zero, the whole conductor, including the surface, is all at the same potential.
 


The charge gets distributed so as to make the surface be an equipotential surface. In presence of an external non-uniform magnetic field, charge density will vary accordingly, to maintain equipotentiality.
 


the choices B and E are a bit ambiguous but i think this is the distinguishing answer your after.
charge on a surface is not spread evenly over the surface, the surface changes to accept the charge placed upon it.
option B suggest charge is spread evenly over surface
option E says surfaces changes such that charge is spread evenly
 

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