When does the surface charge density equal the electric flux density?

Click For Summary
SUMMARY

The discussion centers on calculating the surface charge density and polarization charge density in a parallel plate capacitor filled with polystyrene, which has a relative permittivity of 2.55. Given an electric field intensity of 10 kV/m and a plate separation of 1.5 mm, the surface charge density can be determined using the equation ρs = D · an. The confusion arises regarding the relationship between surface charge density and the electric field at a conducting surface.

PREREQUISITES
  • Understanding of electric field intensity and its units (kV/m).
  • Familiarity with the concept of relative permittivity (dielectric constant).
  • Knowledge of parallel plate capacitor configurations.
  • Proficiency in using the equation for surface charge density (ρs = D · an).
NEXT STEPS
  • Study the relationship between electric field intensity and surface charge density in capacitors.
  • Learn about the effects of dielectric materials on electric fields and charge distributions.
  • Explore the concept of polarization charge density in dielectric materials.
  • Investigate the implications of conducting surfaces on electric field behavior.
USEFUL FOR

Students and professionals in electrical engineering, particularly those focusing on capacitor design, dielectric materials, and electrostatics.

FOIWATER
Gold Member
Messages
434
Reaction score
12

Homework Statement


The electric field intensity in polystyrene (relative permittivity 2.55) filling the space between the plates of a parallel plate capacitor is 10kV/m. The distance between the plates is 1.5mm.
Calculate the surface charge density of free charge on the plates,
and the surface density of polarization charge

Homework Equations


rho s = D dot an

The Attempt at a Solution


---
I am having a hard time seeing how the surface charge density equals the d field normal to the surface in this case?
 
Physics news on Phys.org
Is it because it's at a conducting surface
 

Similar threads

Electric field of a neutral conductor just at the surface
  • · Replies 4 ·
Replies
4
Views
2K
What Are the Electric Field Components at a Charge Density Boundary?
  • · Replies 2 ·
Replies
2
Views
2K
Induced surface charge density
  • · Replies 2 ·
Replies
2
Views
10K
Getting electric potential from charge density over whole sp
  • · Replies 1 ·
Replies
1
Views
2K
Free surface charge density (not bound density)
  • · Replies 2 ·
Replies
2
Views
5K
Surface bound charge on the outer surface of a dielectric
  • · Replies 1 ·
Replies
1
Views
2K
Charge upon a parallel plate capacitor
  • · Replies 18 ·
Replies
18
Views
3K
Capacitor: surface charge densities
  • · Replies 5 ·
Replies
5
Views
5K
I Thought I Understood Gauss' Law (Sheets)
  • · Replies 26 ·
Replies
26
Views
3K
Charge on inner/outer surfaces of two large parallel conducting plates
  • · Replies 11 ·
Replies
11
Views
3K