One thing that has bugged me for some time...

When you calculate a really low corner frequency, like using a really big coupling cap, is it possible to go so big that you let DC through ?

I would first think not based on the function of a cap, but if the capacitor where huge, lets say 1000uf, and you had a resistance to ground of say 38,000hz, your corner frequency theoretically would be a super low .00419hz, so according to the maths result, it's getting close to zero, but I realize it will never actually reach zero, regardless of how big the cap or resistor is. What theory of capacitors allows them to block DC no matter what, (other than exceeding rated voltage or from failure) ?

Thanks for the help in understanding !

When you calculate a really low corner frequency, like using a really big coupling cap, is it possible to go so big that you let DC through ?

I would first think not based on the function of a cap, but if the capacitor where huge, lets say 1000uf, and you had a resistance to ground of say 38,000hz, your corner frequency theoretically would be a super low .00419hz, so according to the maths result, it's getting close to zero, but I realize it will never actually reach zero, regardless of how big the cap or resistor is. What theory of capacitors allows them to block DC no matter what, (other than exceeding rated voltage or from failure) ?

Thanks for the help in understanding !

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