If the cap is polarized, indeed you can.
Some capacitors are not polarized and really don’t care, like this capacitor I just put into the furnace yesterday to replace a bad cap in the main blower motor circuit.
Some caps care very much indeed. Electrolytic capacitors like this one are polarized; note the band with the “-“ sign:
I once carelessly put a cap like this backward on a sex toy I was building. It worked for a minute or two and then the top of the cap blew off with a surprisingly loud “pop!” sound, considering the low voltage and current involved. (I frequently have poor attention to detail.)
So the answer is yes, sometimes. A polarized cap will always be clearly marked, and yes, connecting it backward will most probably destroy it.
article from: https://qr.ae/pF2uTy
Post time: Jun-03-2026