What is the Area of a Capacitor Plate?

  • Thread starter Thread starter warnexus
  • Start date Start date
  • Tags Tags
    Area Plate
Click For Summary

Homework Help Overview

The discussion revolves around calculating the area of capacitor plates using capacitance and related equations. Participants are examining the relationships between charge, voltage, capacitance, and the geometry of the capacitor plates.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the use of capacitance equations and the implications of unit conversions. There is a focus on how to derive the area from capacitance without unnecessary complexity.

Discussion Status

Some participants have identified potential errors in unit conversions and the approach to calculating the area. Guidance has been offered regarding simplifying the calculation process and ensuring consistency in units.

Contextual Notes

There are indications of confusion regarding unit conversions, particularly with metric prefixes, and the need for clarity in the definitions of variables used in the equations.

warnexus
Messages
90
Reaction score
0

Homework Statement



platearea.jpg


Homework Equations


capacitance = charge/volt

capacitance = Esub0 (side of parallel plates^2)/(distance apart)

The Attempt at a Solution



capacitance = (3*10^-6 C)/(150v)
capacitance = 2 * 10 ^ - 8 F

2 * 10 ^ - 8 F = (8.85 * 10 ^ -12)(side of parallel plate) ^ 2/(.90 *10^-2)

side of parallel plate is 20 m ^ 2.
 
Last edited:
Physics news on Phys.org
warnexus said:

Homework Statement



platearea.jpg


Homework Equations


capacitance = charge/volt

capacitance = Esub0 (side of parallel plates^2)/(distance apart)




The Attempt at a Solution



capacitance = (3*10^-6 C)/(150v)
capacitance = 2 * 10 ^ - 8 F

2 * 10 ^ - 8 F = (8.85 * 10 ^ -12)(side of parallel plate) ^ 2/(.90 *10^-2)
Your distance value doesn't look right; check your units conversion. Since you're looking for the plate area anyways, why involve the square of the side length when you can solve directly for the area?

Fix your d value and try again. Make sure that your result description and units match (you reported a side length in square meters before).
 
gneill said:
Your distance value doesn't look right; check your units conversion. Since you're looking for the plate area anyways, why involve the square of the side length when you can solve directly for the area?

Fix your d value and try again. Make sure that your result description and units match (you reported a side length in square meters before).

oops milli is 10^ -3

i found my mistake. plate area = (capacitance)(distance)/(esub0)

plate area = (2*10^-8)(.90 * 10 ^-3)/ (8.85 * 10 ^ -12) = 2 m ^ 2 =]

thanks gneill
 
warnexus said:
oops milli is 10^ -3

i found my mistake. plate area = (capacitance)(distance)/(esub0)

plate area = (2*10^-8)(.90 * 10 ^-3)/ (8.85 * 10 ^ -12) = 2 m ^ 2 =]

Yup, that looks better :smile:
 

Similar threads

Two-layer dielectric, four-capacitor model vs three-capacitor model
  • · Replies 5 ·
Replies
5
Views
1K
Find the electric field between 2 finite discs
  • · Replies 16 ·
Replies
16
Views
2K
Find the charge on the plates of a parallel-plate capacitor w/ dielectric
  • · Replies 3 ·
Replies
3
Views
2K
Parallel-Plate Capacitor Separation
  • · Replies 2 ·
Replies
2
Views
1K
Capacitors: find the dielectric constant
  • · Replies 2 ·
Replies
2
Views
2K
Comparing energy lost by the battery & energy gained by the capacitor.
  • · Replies 5 ·
Replies
5
Views
2K
Parallel plate capacitor voltage question
  • · Replies 8 ·
Replies
8
Views
2K
Max voltage of an air capacitor
  • · Replies 4 ·
Replies
4
Views
2K
Max values for a 2-dielectric capacitor
  • · Replies 21 ·
Replies
21
Views
3K
Equivalent Capacitance of Five Plates with Uniform Area and Spacing
  • · Replies 4 ·
Replies
4
Views
1K