Electrostatics - Charged Plate Force Calculator

AI Thread Summary
A user created a C# app to calculate the force between two oppositely charged plates but doubts the accuracy of its outputs. Forum members point out that the app incorrectly applies the Coulomb force formula meant for point charges rather than charged plates. Questions arise about the user's understanding of significant digits and the meaning of "f/g" in the context of the calculations. Suggestions are made to use tools like Desmos for prototyping and to consult a specific lab exercise for more accurate equations. Overall, the discussion focuses on verifying formulas and improving the app's calculations.
SpiderPig
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Hey everyone,

This is my first post here, please forgive me if it's in the wrong place.

Years ago I made this small app in C# for calculating the force, in Newtons, between two oppositely charged plates that can take various parameters. I've never truly believed the numbers it outputs as they just seem too high to me. I'm curious if anyone here knows a bit about electrostatics and the formulas I've used, and if you'd be kind enough to either verify the formulas or shed some light on where I might have gone wrong. Any thoughts are much appreciated.

Here's a screenshot of the app with some parameters filled in. I'm happy to send the application to anyone who wants to test it out.

Matt

ChargedPlateForceScreenshot.png
 
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You wrote the Coulomb force on one point charge due to another point charge.
That, however, is not the force experienced by one charged plate due to another.

What is meant by f/g? Are you trying to computing the mass of something?

By the way, are you familiar with significant digits?

You can use a tool like Desmos (https://www.desmos.com/calculator) to prototype and to check your work.
 
robphy said:
You wrote the Coulomb force on one point charge due to another point charge.
That, however, is not the force experienced by one charged plate due to another.
Ah I see. Do you know where I might find some helpful information on the equation I need?

robphy said:
What is meant by f/g? Are you trying to computing the mass of something?
Yeah I think my idea here was - if the two plates were horizontal and were attracted to each other, how heavy an object can the bottom plate hold up without it separating.

robphy said:
By the way, are you familiar with significant digits?
No, I've not heard of the term before... am I displaying the results incorrectly?

robphy said:
You can use a tool like Desmos (https://www.desmos.com/calculator) to prototype and to check your work.

Cool, I'll use that! Many thanks!
 
Thankyou!
 

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