Solutions to laplace's equation & uniqueness thrm #2 (Griffiths)

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SUMMARY

The discussion centers on the second uniqueness theorem for solutions to Laplace's equation as presented in Griffiths' "Introduction to Electrodynamics" (4th edition), specifically in Chapter 3, page 121. The theorem states that in a volume V surrounded by conductors with a specified charge density ρ, the electric field is uniquely determined if the total charge on each conductor is known. The charge density ρ refers to the region within volume V, not the conductors. Additionally, it is confirmed that uniqueness theorem 1 applies to both Laplace's and Poisson's equations, while uniqueness theorem 2 is specific to Poisson's equation.

PREREQUISITES
  • Understanding of Laplace's equation and Poisson's equation
  • Familiarity with electrostatics concepts, including electric fields and charge density
  • Knowledge of the uniqueness theorems in electrostatics
  • Basic comprehension of Griffiths' "Introduction to Electrodynamics" (4th edition)
NEXT STEPS
  • Study the derivation and applications of Laplace's equation in electrostatics
  • Explore the implications of Poisson's equation in charge distributions
  • Review the uniqueness theorems in electrostatics for deeper understanding
  • Examine examples of electric fields in conductor configurations
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Students and professionals in physics, particularly those focusing on electromagnetism, as well as educators teaching electrostatics concepts and the mathematical foundations of electric fields.

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In griffith's intro to electrodynamics (4rth edition), ch. 3, pg. 121.

here is the second uniqueness thrm for the solutions to laplace's equation:

Second uniqueness thrm: In a volume V surrounded by conductors and containing a specified charge density ρ, the electric field is uniquely determined if the total charge on each conductor is given.

the only part I'm confused about is, in the beginning where he says "in a volume V surrounded by conductors and containing a specified charge density ρ"

Q: is the charge density ρ referring to that belonging to the region of space whose potential we're trying to determine? or is it referring to that of the conductor/insulator?

thanks
 
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It is referring to that belonging to the volume V in which we are solving for the electric field.
 
thought so!

but then this leads to another confusion. I thought both uniqueness theorems were meant for the solutions to the laplace equation. The laplace equation however does not deal with charges inside the region.

so then, i guess, uniqueness thrm 1 is for both the laplace & the poisson equations while uniqueness thrm 2 is for just the poisson eqn?

please confirm this for me
 
Uniqueness theorem 2 is for Poisson's and uniqueness theorem 1 is for Laplace's.
 

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