Gauss Law in a plane sheet, and thick sheet (Infinite)

Click For Summary
SUMMARY

The discussion centers on Gauss's Law as applied to a plane sheet of charge, presenting two key formulas: E=σ/ϵ for a thick sheet and E=σ/2ϵ for a negligible thickness sheet. The participant expresses confusion regarding the relationship between electric field strength (E) and the distance from the charge, questioning why the inverse square law appears to be disobeyed. It is clarified that while individual charge contributions follow the inverse square law, the geometry of the setup alters the overall relationship, which is supported by additional resources provided.

PREREQUISITES
  • Understanding of Gauss's Law
  • Familiarity with electric field concepts
  • Knowledge of charge distribution and density (σ)
  • Basic grasp of geometry in physics
NEXT STEPS
  • Study the derivation of Gauss's Law in different geometries
  • Explore the relationship between electric fields and charge distributions
  • Investigate the implications of geometry on electric field strength
  • Review the provided resource on charged planes for deeper insights
USEFUL FOR

Physics students, educators, and anyone interested in electrostatics and the application of Gauss's Law in various charge configurations.

Prannoy Mehta
Messages
94
Reaction score
2
We have learned the below formula for a plane sheet of charge with thickness.

E=σ/ϵ

and the one below for with no thickness (negligible)

E=σ/2ϵ

The problem, I am facing is digesting the derived equations. It is one thing for sure that these formulas must be right. But then the fact that E is proportional to the square of the distance between the test charge (Or any other charge, taken from columbs law.) is disobeyed by it (Atleast that's what I think.) I have seen alternate derivations with the same expression. Why is this not obeyed, or is it obeyed over here.

Thank you.
 
Physics news on Phys.org
The contribution from each individual charge does obey the inverse square law, but the geometry of the situation leads to the result.
This might help
http://mlg.eng.cam.ac.uk/mchutchon/chargedPlanes.pdf
Notice that the sin θ term increases with the distance from the plate and this counteracts the inverse square relationship.
 
Thanks a tonne :D
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 6 ·
Replies
6
Views
554
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 2 ·
Replies
2
Views
5K
  • · Replies 26 ·
Replies
26
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K