Electric field strength between charged plates

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SUMMARY

The discussion centers on the electric field strength between charged plates, specifically addressing the misconception that electric field strength decreases with distance. The correct understanding is that while the equation E = kq/r² applies to point charges, the electric field between parallel plates remains relatively constant regardless of distance. Participants emphasized the importance of visualizing field lines and understanding the geometry of the system, particularly in relation to Gaussian surfaces in electrostatics.

PREREQUISITES
  • Understanding of electric field concepts
  • Familiarity with the equation E = kq/r²
  • Knowledge of Gaussian surfaces in electrostatics
  • Ability to sketch electric field lines
NEXT STEPS
  • Research the behavior of electric fields between parallel plates
  • Study Gaussian surfaces and their applications in electrostatics
  • Learn about the concept of electric field line density
  • Explore different geometries of charge distributions and their effects on electric fields
USEFUL FOR

Students studying electrostatics, physics educators, and anyone seeking to deepen their understanding of electric fields and their behavior in various configurations.

Cici2017

Homework Statement


Screen Shot 2017-07-31 at 6.50.30 pm.png


Homework Equations

The Attempt at a Solution


E=kq/r2
so when the distance increase E should decrease?
I know this is wrong, but can someone explain why? Thanks
 
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Cici2017 said:

Homework Statement


View attachment 208034

Homework Equations

The Attempt at a Solution


E=kq/r2
so when the distance increase E should decrease?
I know this is wrong, but can someone explain why? Thanks
Have you tried sketching the field lines?
 
haruspex said:
Have you tried sketching the field lines?
field lines are from + to negative. vertical.
 
Cici2017 said:
field lines are from + to negative. vertical.

The field strength is equal to the density of the field lines, what can you say about that if all the field lines are vertical?
 
Have you covered gaussian surfaces in electrostatics yet?
 
Cici the field at any point depends, amongst other things, on the geometry of the system. The equation you used gives the field due to an isolated point charge. And yes,this particular field does weaken with distance. The field for other geometries is different so for your parallel plates take the advice given above.
 
I think I have got it. Thank you!
 

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