Two quick questions conerncing potential and dielectric

AI Thread Summary
The discussion addresses two questions regarding electric potentials and dielectrics. It confirms that the potential is steady at the boundary (x=0) between a dielectric and air, as electrostatic potential is continuous across the interface. The potential indeed depends on the relative permittivity, similar to the electric field, which is weakened in a dielectric medium. The potential from a point charge varies along the x-axis but remains consistent at the boundary. Overall, the interface between two media maintains a continuous electrostatic potential.
Lindsayyyy
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Hi everyone,

I have a question about electric potentials and dielelectrics:

1. when I have a dielectri in the half space x<0 and air in x>0 is the potential steady at x=0?

2. does a potential depend on the relative permittivity ?


I know that the electric field gets weaker in a dielectric with 1/epsilon_r but what about the potential? I'm not sure here.

Thanks for your help in advance.
 
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1. What electric field is applied?
2. Yes, it does in the same way as electric field.
 
lets just talk about a general potential like

\Phi (\vec r) = \frac {1}{4\pi \epsilon_0} \frac {q}{|\vec r -\vec r_0|} for x >0 and for x<0 the same one (+ epsilon_r for the permittivity).

are these potentials steady at x=0 ?
 
This is a potential from a point charge. It's value changes along X axis.
 
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The electrostatic potential is continuous at the interface of two media. In your problem, it is the same at x=0 at both sides of the boundary.

ehild
 
thank you very much.
 
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