Timeline for Why aren't wires capacitors?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Feb 1, 2014 at 3:00 | comment | added | Peter Bennett | @dfg: the small capacitors you've seen have several layers of plates/insulators, giving a much larger effective area than might appear, and the insulators between plates are very thin, further increasing capacitance. | |
| Jan 31, 2014 at 23:45 | comment | added | markrages | The plates in a capacitor are really close together, much closer than wires on a PCB. | |
| Jan 31, 2014 at 22:56 | comment | added | dfg | 1) If the wires are right beside each other (like in a circuit board), the distance is around the same as a capacitor. 2) The capacitors I've seen are small, around the same size as a big wire. So what's makes the wires any difference that a normal capacitor? | |
| Jan 31, 2014 at 22:51 | comment | added | Peter Bennett | @dfg: the capacitance between two objects is proportional to the area of the objects, and inversely proportional to the distance between the objects, and also depends onthe material between the object. A capacitor will have a large plate area, with very closely placed plates, to give a large capacitance relative to its size. The wires have a relaitvely small effective area, and are much farther apart than the capacitor plates, so the capacitance between the wires will normally be much less than that of the capacitor. | |
| Jan 31, 2014 at 22:32 | comment | added | dfg | But why wouldn't it spread out? For instance, see the diagram I added (the hand drawn one). The wires are really close so the charge would feel the same field at any point on the wire. So why would they gather at the capacitor? And why wouldn't the capacitance be significant? | |
| Jan 31, 2014 at 22:27 | history | answered | Turbo J | CC BY-SA 3.0 |