capacitor with one long leg and one short leg

"ok"




** With normal electro caps, the shorter lead is negative -  there is a
  " - "   sign on the body as well.

 With bi-polar electros it does not matter at all.





.......    Phil

somebody

The long leg.

Assuming that they're electrolytics. (Shaped like a tin can, either
two legs from one end, or a leg at each end.)

The long leg is the postive (+) lead. There will also usually be a
very wide & visible black stripe running along one side of the
capacitor which will indicate the positive lead, or will have a symbol
"(-)" & an arrow ">" pointing towards the negative lead.

As someone has already mentioned, bipolar electros can be placed
either way around, *but* make sure that they *are* bipolar cap's
before soldering them in, because a normal (polarised) electro will go
*BANG!* if you put it in backwards & power it up! Bipolar electros
will normally be clearly marked with the word "bipolar" on the label.

It is written on the body of cap. I assume you are talking about
electrolitic ones. '-' is shown on the body. If cap is bi-polar, it does not
matter how you insert it.

Rudolf