Dielectric interface plate capacitor at angle alpha

AI Thread Summary
The discussion focuses on determining the electric field (E-field) inside and outside a tilted dielectric interface in a plate capacitor. The initial analysis reveals that the parallel component of the E-field inside the dielectric is zero when the angle alpha is zero, while the perpendicular component is related to the permittivities of the two media. The participants explore how to extend these findings to other angles by adjusting the equations for non-zero angles. Additionally, they discuss the behavior of the E-field vector as it transitions between media with different permittivities, including resolving the vector into normal and tangent components. The conversation emphasizes the importance of verifying calculations by ensuring that the potential difference remains consistent along different paths.
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Homework Statement
Consider a plate capacitor with a dielectric interface (\epsilon = \epsilon_0*\epsilon_r, thickness=d) tilted at the angle \alpha . Outside the interface \epsilon = \epsilon_0. Without dielectric interface is the field \vec{E}=E_0*\vec{e_z}. Determine the E-field inside and outside the dielectric interface at the angle \alpha.
Relevant Equations
E_1*sin a_1= E_2* sin a_2
TheoAufgabe.png

Consider a plate capacitor with a dielectric interface (\epsilon = \epsilon_0*\epsilon_r, thickness=d) tilted at the angle \alpha . Outside the interface \epsilon = \epsilon_0. Without dielectric interface is the field \vec{E}=E_0*\vec{e_z}.
Determine the E-field inside and outside the dielectric interface at the angle \alpha (a).
My first attempt was to determine the E-field for the parallel and the perpendicular component at the angle \alpha=0 inside and outside the medium.
Inside the medium:
for the parallel component→ E_1*sin a_1= E_2* sin a_2 with a_1 = 0 → E_2=a_2=0
So inside the dielectric interface the parallel component is zero
for the perpendicular component: epsilon_1*E_1*cos a_1 = epsilon_2*E_2*cos a_2 with a_1= 0 → E_2=epsilon_1/epsilon_2* E_1
Outside the medium the electric displacement field D represents how an electric field E influences the organization of electric charges in a given medium. In electric field is D = epsilon_0*E +P.
But how do I determine the field for any other angle alpha ? Could I use the equations from the first attempt with a_1≠0 ?
 
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lena_2509 said:
Homework Statement: Consider a plate capacitor with a dielectric interface (\epsilon = \epsilon_0*\epsilon_r, thickness=d) tilted at the angle \alpha . Outside the interface \epsilon = \epsilon_0. Without dielectric interface is the field \vec{E}=E_0*\vec{e_z}. Determine the E-field inside and outside the dielectric interface at the angle \alpha.
Homework Equations: E_1*sin a_1= E_2* sin a_2
View attachment 250691
What changes occur to an E vector normal to an interface between media of differing permittivities as it passes from one medium to another?

What changes occur to an E vector tangent to an interface between media of differing permittivities as it passes from one medium to another?

Can you resolve an oblique E vector into normal and tangent components, determine those changes, and from them determine the new E vector magnitude and direction inside the dielectric?

And can you check your work by line-integrating the new E vector along its new zig-zag path to verify that the potential difference between the plates is the same along this new path as it is along a path well beyond, and outside, the dielectric?
 
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