I know what a Farad is, and what a Coulomb is. In fact, I've just finished reading both entries in the Wikipedia before coming here to refresh my memory, and to assure everyone that I've done my bit of research before posting my question:
Starting from the definitions:
One Coulomb = 1*F*V, or 1*A*s
One Farad = 1*A*s/V (among other definitions)
My question here is, why is it sometimes better to express things in Coulombs than in Farads and vice-versa? Why is a capacitor's capacitance better expressed in Farads? Why not use Coulombs instead?
I'm under the impression that it's easier for a scientist or engineer to visualize things depending on the chosen units. For instance, a Co2 laser's power is normally expressed in Watts, whereas a Ruby's is preferably expressed in Joules. That is because a Co2 laser has a continuous output, while a Ruby laser works in very short pulses. And although those pulses do span a certain amount of time, (and therefore its power can also be expressed in Watts) it's easier to visualize a Ruby laser's power as an instantaneous burst of energy. That's why Joules come into play.
Is that why a mosfet's gate capacitance is expressed in Farads, while a transistor's in Coulombs?
Starting from the definitions:
One Coulomb = 1*F*V, or 1*A*s
One Farad = 1*A*s/V (among other definitions)
My question here is, why is it sometimes better to express things in Coulombs than in Farads and vice-versa? Why is a capacitor's capacitance better expressed in Farads? Why not use Coulombs instead?
I'm under the impression that it's easier for a scientist or engineer to visualize things depending on the chosen units. For instance, a Co2 laser's power is normally expressed in Watts, whereas a Ruby's is preferably expressed in Joules. That is because a Co2 laser has a continuous output, while a Ruby laser works in very short pulses. And although those pulses do span a certain amount of time, (and therefore its power can also be expressed in Watts) it's easier to visualize a Ruby laser's power as an instantaneous burst of energy. That's why Joules come into play.
Is that why a mosfet's gate capacitance is expressed in Farads, while a transistor's in Coulombs?
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