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

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The discussion focuses on the electric field E(x) and potential V(x) between two thin charged metal plates positioned at x = 0 and x = d. The surface charge density is defined as σ = Q/A, leading to the conclusion that E(x) = σ/ε₀ for the region 0 < x < d, with V(x) derived as V(x) = (σ/ε₀)x. For regions outside the plates (x > d and x < 0), the electric field is zero, while the potential remains continuous across the surfaces. The confusion arises regarding the correct expressions for E and V outside the plates, emphasizing the need for clarification on these points. The discussion highlights the importance of accurately deriving these expressions to facilitate further analysis and sketching of the electric field and potential.
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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 \sigma = \frac{Q}{A}

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

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!
 

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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.
 
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