Electric Field and Potential of Thin Charged Metal Plates: Analysis and Sketch

Click For Summary
SUMMARY

The discussion focuses on the electric field E(x) and electric potential V(x) of two thin charged metal plates positioned at x = 0 and x = d. Using Gauss's Law, the electric field within the plates is determined as E(x) = σ/ε₀, where σ is the surface charge density. The potential is derived as V(x) = (σ/ε₀) x for 0 < x < d. Outside the plates, specifically for x > d and x < 0, both the electric field and potential are zero, confirming the discontinuity of the electric field due to the charge distribution.

PREREQUISITES
  • Understanding of Gauss's Law
  • Familiarity with electric field and potential concepts
  • Knowledge of surface charge density calculations
  • Basic calculus for integration of electric fields
NEXT STEPS
  • Study the application of Gauss's Law in electrostatics
  • Learn about electric field and potential relationships in different geometries
  • Explore the concept of surface charge density in conductive materials
  • Investigate the continuity of electric potential across boundaries in electrostatics
USEFUL FOR

Students and professionals in physics, electrical engineering, and anyone studying electrostatics, particularly those interested in the behavior of electric fields and potentials in charged conductors.

stunner5000pt
Messages
1,447
Reaction score
5
Two thin long charged metal plates are placed at x = 0, and x = d (that means they are plaed vertically, parallel to the Y Axis. Thus the distance between them is d. Assume that V(x=0) = 0, and that the thickness of the plates is lesser than d.

a) Find E(x) and V(x) when 0 < x < d.

First of all let the surface charge density [tex]\sigma = \frac{Q}{A}[/tex]

If i use Gauss Law then the Electric field [tex]E = \frac{\sigma}{\epsilon_{0}}[/tex] since the plates are conducting surfaces.
To find [tex]V(x) = \int E \cdot dx = \frac{\sigma}{\epsilon_{0}} \cdot dx = \frac{\sigma}{\epsilon_{0}} x[/tex]

i'm not really sure if i derived that expression correctly for V(x) which i why i need your help, please.

b) Find E(x) and V(x) if x > d
E(x>d) = zero or kq / (x+d)^2
V(x>d) = zero as well? or simply integrate E over x??

c) Find E(x) and V(x) if x<d
same as the previous one?? i.e. both E and V are zero?? Not really sure here either?

d) Sketch E(x) and V(X)
I m not really sure about my expressions in a so if i found those out properly, with your help i can easily do this one!

Thank you in advance for your help!
 

Attachments

  • untitled.JPG
    untitled.JPG
    7.8 KB · Views: 490
Last edited:
Physics news on Phys.org
so is ther anyone out there who can help me!

i am cofnused about hte first part whether E = kq/r^2 or E = constnat

but then the graphing part would be useless no?

And wha about the outsides of the plates?
 
Your E field and potential for the middle region (0 < x < d) are correct!

For x > d the electric field will be zero (it's discontinous due to the charge) and likewise for x < 0. However, the potential will be continuous across those surface.
 

Similar threads

Replies
4
Views
4K
  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 26 ·
Replies
26
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 18 ·
Replies
18
Views
2K
Replies
1
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K