Capacitance

[rlaboss]

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Can anyone explain to me why capacitance increases as two plates are moved closer together? I understand how to manipulate the C = kEoA/D formula but I can't conceptualize the relationship between distance and capacitance. Thanks!

 

[Bubbada_G]

The closer the charges the stronger he attractive force between them. Making it less likely for a charge to move away, and more likely to stay put = greater charge held

 

[Troll-like receptor 4]

Well, the further away the plates are, the more difficult it is to store charge (which is basically what capacitance is about. Neurons are a good example of this. Myelination decreases capacitance, because opposite charges are more separated, which means less attraction. This is what increases conduction velocity because the depolarization is able to spread and propagate due to charge-charge repulsion.

This is why capacitors in series result in overall decreased capacitance. The middle plates in essence cancel each other out, and the outer two plates in series configuration form the effective distance.

Capacitors in parallel increase overall capacitance because you take the sum of the surface areas of all the plates, and this is directly proportional to capacitance. Hopefully this helps. ☺