Dave Plowman (News) wrote:

In article ,
"Pet @ www.gymratz.co.uk ;¬)" wrote:

Yes, to a DC voltage a Capacitor has infinite resistance because it is
open circuit!

Eh?

But if the 'DC' voltage changes a current will flow, so you can no
longer describe it as presenting infinite resistance - although of
course energy is being stored or released, rather than dissipated as
heat as it would be in a resistor.

For a perfect capacitor i = C * dv/dt, for a practical capacitor there's
always some additional loss present which does result in heat being
dissipated. This is usually thought of in terms of an equivalent series
resistance, ESR.

There's no such thing as DC really, unless you've been hanging around
since before the big bang.

--
Andy