What is the total charge on the surface?

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SUMMARY

The total charge on the surface of a sphere with a point charge q at its center, embedded in a linear dielectric material, is zero. This conclusion arises from the calculation of the surface polarization charge density, which results in a value of zero due to the absence of surface polarization. The compensating negative bound charge is located at the center of the sphere, coinciding with the position of the point charge q. The analysis utilizes the concepts of volume polarization charge density and surface charge polarization density within the context of dielectric materials.

PREREQUISITES
  • Understanding of linear dielectric materials and susceptibility (chi(e))
  • Familiarity with the concepts of polarization charge density
  • Knowledge of Gauss's Law in electrostatics
  • Basic calculus for evaluating derivatives in charge density calculations
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  • Study the implications of Gauss's Law in dielectric materials
  • Learn about the relationship between electric displacement field (D) and polarization (P)
  • Explore the concept of bound charges in dielectrics
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Homework Statement


A point charge q is embedded at the centre of a sphere of linear dielectric material (with susceptibility chi(subscript e) and radius R).

b)What is the total charge on the surface? [3 marks]
c) where is the compensating negative bound charge located? calculate it


The Attempt at a Solution



volume polarisation charge density=-div P
=1/r^2 d/dr((r^2)P) (partial derivative)
=1/r^2 d/dr [[(r^2 Q chi(e) epsilon0]/[4 pi epsilon(r) r^2]]
=1/R^2 d/dr [(q chi(e) epsilon0)/(4 pi epsilon (r))]
=1/R^2 *0
=0


surface charge polarisation density=[(q chi(e) epsilon0) r-hat.n]/(4 pi epsilon1 R^2)
=[(q chi(e) epsilon0)]/(4 pi epsilon1 R^2)

does that help to calculate the total bound charge on the surface at all?
because the surface polarisation charge density=0, the bound charge on the surface=0. three marks for saying just that?

please tell me if I'm wrong
 
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, I'm not confident about this. c) The compensating charge is located in the interior of the sphere i.e. at the position of the point charge q.
 

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