Understanding the Units of Permittivity of Free Space in Coulomb's Law

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SUMMARY

The discussion centers on the physical significance of the permittivity of free space (ε₀) in Coulomb's Law and its role in capacitance calculations. The capacitance (C) of a parallel plate capacitor is directly proportional to the permittivity (ε₀) and the area (A) of the plates, while inversely proportional to the distance (d) between them, as expressed in the formula C = ε₀(A/d). The units of ε₀, measured in farads per meter (F/m), derive from this capacitance relationship and the speed of light equation c = 1/√(ε₀μ₀). A clarification was made regarding the correct representation of the formula in Coulomb's Law, emphasizing the need for accurate notation.

PREREQUISITES
  • Understanding of capacitance and its formula C = ε₀(A/d)
  • Familiarity with the concept of permittivity of free space (ε₀)
  • Knowledge of Coulomb's Law and its mathematical representation
  • Basic grasp of electromagnetic theory, particularly the relationship between ε₀ and μ₀
NEXT STEPS
  • Study the derivation of the capacitance formula C = ε₀(A/d) in detail
  • Explore the implications of permittivity in electromagnetic theory
  • Learn about the speed of light and its relationship to ε₀ and μ₀
  • Investigate common misconceptions in the application of Coulomb's Law
USEFUL FOR

Students of physics, electrical engineers, and anyone interested in understanding the principles of capacitance and the role of permittivity in electromagnetic interactions.

wasi-uz-zaman
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Hi please tell me physical significance of permittivity of free space, how can we explain its value having unit of F/m
 
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Creating a capacitor with "free space" as the dielectric (or any sort of dielectric), the capacitance is proportional with the permittivity, the area (m2) and inverse proportional with the distance between the plates (m). Therefore, to calculate the capacitance, you multiply with the area and divide by the distance - and you end up with the capacitance (in F).
 
In a parallel plate capacitor, lines of flux reach across the void to terminate on charges of opposite sign on the opposing plate.
Svein has ably demonstrated the units of ##\epsilon## based on the formula for capacitance, ##C=\epsilon\frac{A}{d}##

The units of ##\epsilon## are not so obvious if you try deconstructing this speed of light formula, ##c=\dfrac 1{\sqrt{\epsilon\mu}}##
 
Changing the topic,in coulumbs law
1\4 pi epselon = 9x10^9 but on solving I'm not getting the same
 
helter skelter said:
Changing the topic,in coulumbs law
1\4 pi epselon = 9x10^9 but on solving I'm not getting the same
If this is a new topic, you need to start a new thread.

If this is still on the units of permittivity, explain what it is you are trying to solve.

I doubt the formula could be 1\4 pi epsilon. It is almost surely 1/(4 pi epsilon).
 

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