analogizing logic gates

[PG1995]

Hi

How would you analogize logic gates? For example, voltage could be though of as a pressure, transistor could be thought of as device with three gates where middle gate control anything passing thru other two gates, diode could be though as valve which lets flows only in one direction. Perhaps, my examples are not very precise and accurate but you get the idea what I'm after. Thank you.

 

[alec_t]

AND gate: Two taps in series in a length of pipe.
OR gate: Two taps, each in a different arm of a T-junction on a pipe.
NOT gate: One tap controlling a hydraulic ram (or diaphragm valve) which turns off another tap.

 

[cr0sh]

If you want working physical models of such gates - check into "fluidics":

https://en.wikipedia.org/wiki/Fluidics

On another note, the April 1988 Scientific American published A. K. Dewdney's article, "Computer Recreations: An ancient rope-and-pulley computer is unearthed in the jungle of Apraphul"; of course, it's an April Fools joke, but it also manages to explain in great detail the basics of logic gates, while presenting a completely theoretical method of constructing such gates (and ultimately a computer) using nothing more than ropes, pulleys, and other simple machines (ultimately it would never work, at least with regular sized ropes, etc - friction and other issues would cause massive losses before you got anything working; then again, properly constructed, a mechanical binary computer is possible, as Konrad Zuse showed).

 

[carbonzit]

... transistor could be thought of as device with three gates where middle gate control anything passing thru other two gates ...

Actually, I'd look at a transistor as a single valve (E--> C), with the base as the "handle" of the valve. Base voltage "turns the handle", which allows current (liquid) to flow from emitter to collector (or C--> E for "conventional" current flow).