[sdiy] Wanted: non mathematical description of the function of RC-filters

[Thomas Strathmann]

On 09.08.13 12:44, Tom Wiltshire wrote:
> I agree with Ingo. I think many of these physical models people are offering as explanations are no more intuitive than the actual situation. I can see no reason why mechanics is easier to "get". Galileo spent quite a long while trying to convince people that light objects and heavy objects fell at the same speed, for instance. Everyone thought it was intuitively obvious that heavy things fall quicke

I have never been fond of mechanical or other models that try to explain
the way that circuits or individual components work. As a child I had
one of those Kosmos kits with lots of parts and I simply could not
understand why they chose to explain the principles of transistors using
little electrons with eyes, arms and legs and water flowing in canal
systems M. C. Escher would have been proud of, or why they explained
feedback (in op amp circuits) with a cow that drinks its
own milk. Years later all this began to make sense but I still don't
think those analogies were particularly good for building understanding
but they stick with you. Sometimes an analogy is just that: A picture
that stays with you and acts as a sort of reminder. I try to incorporate
that into explanations I give to students without claiming that they are
the real thing or give a precise explanation of the concept at hand. And
that's for math devoid of any physical interpretation. Come to think of
it: Sometimess, when the math becomes so abstract that you think you
cannot bear it anymore (case in point: category theory), you realise
that you've come full-circle and what you are doing actually has a
precise correspondence with geometry and you can draw pretty pictures
that are literally the same as a formula or two. Perhaps one could do
something similar with the "math" involved in simple circuits? How would
you visualise the equations?

	Thomas