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Femme_physics
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Understanding "capacitance" formula
In this formula
http://img810.imageshack.us/img810/9127/capacitance.jpg 1) What does it mean the area of overlap of the two plates? Does it mean the "area" of the plates? And, is the area of one plate always the same size of the other plate?
And also,
2) The distance between the plates is measured is what, normally? mm?
And they also said that "εr is the relative static permittivity (sometimes called the dielectric constant) of the material between the plates (for a vacuum, εr = 1);"
So my last question:
3) In a vacuum there is no static permittivity or that there is maximum static permittivity? If what I understand static permittivity is pretty much like the ability to store charge...? So, vacuum has no ability to store charge...shouldn't it be zero?
PS and while I'm at it, is the time constant measured only in seconds?
In this formula
http://img810.imageshack.us/img810/9127/capacitance.jpg 1) What does it mean the area of overlap of the two plates? Does it mean the "area" of the plates? And, is the area of one plate always the same size of the other plate?
And also,
2) The distance between the plates is measured is what, normally? mm?
And they also said that "εr is the relative static permittivity (sometimes called the dielectric constant) of the material between the plates (for a vacuum, εr = 1);"
So my last question:
3) In a vacuum there is no static permittivity or that there is maximum static permittivity? If what I understand static permittivity is pretty much like the ability to store charge...? So, vacuum has no ability to store charge...shouldn't it be zero?
PS and while I'm at it, is the time constant measured only in seconds?
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