
Two-Terminal Components
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If we try to measure the resistance of a capacitor, it starts from a low value
and, after a while, it results in an innite value.
This is because the instrument provides a DC current and, measuring the volt-
age drop, determines the value of the resistance. As a consequence, the current
charges the capacitor which, when completely charged, does not allow any more
current to ow. According to Ohm’s law, no current means innite resistance.
Curiosity
Capacitors are occasionally referred to as condensers, which is actually an
older term used by Volta in 1782. This was because electricity was thought to
be a sort of “uid” ...