On Mon, 30 Jan 2006 00:12:52 +0100 fons adriaensen <fons.adriaensen@xxxxxxxxx> wrote: > On Sun, Jan 29, 2006 at 10:55:05PM +0000, Folderol wrote: > > > No! It is definitely 1/c1 + 1/c2 ... > > > > The only alternative I know of is 'product divided by sum' which is > > often easier to use. > > > > i.e. > > > > (c1 x c2 x c3) / (c1 + c2 + c3) > > Sorry, all wrong, as can be seen easily by considering the dimensions. > The first one is 1/Farad, the second Farad^2. > > The rule is the same as for parallell resistors: > > The inverse of the equivalent value is the sum of the inverses > of all individual values. > > 1/Ceq = 1/C1 + 1/C2 + 1/C3 + ... > > or for just two of them > > Ceq = (C1 * C2) / (C1 + C2) Apologies. I'm out of practise :( I was *assuming* the 1/Ceq = and we all know about when you ASS U ME. As you say the second one is strictly for two components. -- F
