What is the Relationship between E, D and P in a Material?

  • Thread starter Roodles01
  • Start date
  • Tags
    Material
In summary, A thick sheet of polystyrene with a relative permittivity of 2.5 is placed in a uniform electric field of 500Vm−1 in air. The magnitudes of the electric field, electric displacement, and polarization inside the material can be found using the equations D = εε0E and D = ε0E + P. The boundary conditions for D are Doutside = Dinside, which leads to the equation εoutEout = εε0Ein. With the given values, the electric field inside the material is 200 Vm-1 and the electric displacement is 1.77x10-9. To calculate the polarization, the equation D = ε0E + P is
  • #1
Roodles01
128
0
A problem involving E, D & P. I have the answer but not sure why for the P bit.A bit of clarification if someone could, please.

A thick sheet of polystyrene, of relative permittivity ε = 2.5, is placed
normal to a uniform electric field of magnitude 500Vm−1 in air.

Find the magnitudes of the electric field E, the electric displacement D and the polarization P inside the material.

OK div D = ρf
and D = εε0E
Boundary conditions Doutside = Dinside → εoutEout = εε0Ein

so
Ein = Eout / ε
Ein = 500/2.5
Ein = 200 Vm-1

Dout = Din = ε0 Eout
Dout = 8.85x10-12 x 200
Dout = 1.77x10-9


Fine so far . . .

When I get down to calculating P I have to use

Din = ε0Ein + Pin

why, when everything else has the suffix "in" do I use ε0? Shouldn't it be just plain ε?

Thanks in advance.
 
Physics news on Phys.org
  • #2
I'm sorry you are not finding help at the moment. Is there any additional information you can share with us?
 
  • Like
Likes 1 person

Related to What is the Relationship between E, D and P in a Material?

1. What is the significance of "E, D, and P" inside a material?

"E, D, and P" inside a material refer to the electric field, electric displacement, and polarization, respectively. These are important properties of a material that determine its behavior when subjected to an electric field.

2. How do these properties affect the overall behavior of a material?

The properties of "E, D, and P" inside a material are closely related to each other and affect the material's dielectric constant, resistivity, and other electrical characteristics. These properties also determine the material's response to an applied electric field, such as its ability to store charge or conduct electricity.

3. How are "E, D, and P" measured in a material?

There are various methods for measuring "E, D, and P" inside a material, including capacitance measurements, dielectric spectroscopy, and polarization measurements. These techniques involve applying an electric field to the material and measuring its response.

4. Can "E, D, and P" be manipulated or controlled in a material?

Yes, "E, D, and P" can be manipulated or controlled in a material through various methods such as applying an external electric field or changing the temperature or pressure. This can lead to changes in the material's electrical properties and behavior.

5. What are the practical applications of understanding "E, D, and P" inside a material?

Understanding "E, D, and P" inside a material is crucial for developing and improving various technologies, such as capacitors, sensors, and electronic devices. It also plays a vital role in fields such as materials science, electrical engineering, and physics.

Similar threads

Maxwell's Equations, Dielectrics, Auxiliary Fields D and H
    • Electromagnetism
Replies
16
Views
1K
What is Permittivity? Definition & Explanation
    • Other Physics Topics
Replies
1
Views
3K
Polarization charge density of homogeneous dielectric
    • Electromagnetism
Replies
3
Views
2K
What is the weird field in dielectrics?
    • Electromagnetism
Replies
6
Views
850
Electric field in a cavity in a spherical charge density
    • Introductory Physics Homework Help
Replies
2
Views
1K
Electrostatics/Magnetostatics - E,D,P and B,H,M
    • Electromagnetism
Replies
1
Views
2K
What is susceptibility in physics?
    • Other Physics Topics
Replies
1
Views
20K
On the Electric Displacement Vector D=E+4*pi*P
    • Electromagnetism
Replies
5
Views
3K
Parallel Plates, Capacitor and Dielectrics
    • Introductory Physics Homework Help
Replies
3
Views
1K
Definition of Conductor: What is a Conductor?
    • Other Physics Topics
Replies
1
Views
1K

Hot Threads

Recent Insights

Back
Top