I want to write briefly on how to make a capacitor.Capacitors are sometimes colored-coded but more usually they have the value printed on the body.There is a good deal of variation between makers exact form of the markings but most use the normal units of picofarad (pF),nanofarad (nF) or the microfarad (µF).
There are many kinds of capacitors,but they all do the same thing:store electrons.The simplest capacitor is two conductor separated by an insulated materials called the Dielectric like diagram below:
The dielectric can be paper ,plastic film,Mica,glass,ceramic,air or a vacuum discs,aluminium foil, or a thin film of metal applied to opposite sides of a solid dielectric.The conductor-dielectric-conductor sandwich can be rolled into a cylinder or left flat.
Capacitor can be made with two sheets of aluminium foil and one sheet of waxed paper .Fold the paper around one foil sheet and stack the sheets like diagram below:
Then fold the sheets like diagram below:
Be sure the foil sheets do not touch! press the contact of 9-volt battery briefly to the exposed ends of the foil sheets.Then touch the probe of a high-impedance multi-meter to the foil sheets.The meter will indicate a small voltage for a few seconds.The voltage will then fall back to zero.
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