A capacitor also has a very non-constant r, this time it
depends not on the temperature but on the applied DOP.
The V/I decreases rapidly when the DOP approaches the
maximum allowed value. It was quite common, when
we were measuring the ratios, to see them decrease by
an order of magnitude when the DOP changed by 10%.
The V/I is usually called the "leakage resistance, r". Is
this an appropriate term? What is a better name?
P.S. No I am not referring to capacitors in series.
It is a simple RC circuit with r (in a model) parallel
with C. The dependence of r on V complicates the
mathematics of charging; the assumption that R<<r
becomes not valid at some point. The assymptotic
current is not zero. Nothing profound; everybody
knows that models are only approximations. And
nobody objected to a model according to which
light bulbs are devices whose R depends on I. Is
this a correct assesment of the current thread? The
issue seems to be "to call a common light bulb a
resistor or not (when light is produced)?" It is not
a resistor because it does not obey "Ohm's relation"
of direct proportionality between V and I. Right?
Ludwik Kowalski