Post by @tubetime@mastodon.social
new book just landed on my bench: The Secret Life of Circuits, by @lcamtuf ! (soldering iron not included)
it has some neat illustrations, including this one of a toilet. (the book makes a point about avoiding any form of the water analogy)
@tubetime Is there something wrong with the water analogy? I hear people pooh-poohing it a lot, but it's always seemed a good enough way to develop a basic intuition if someone is not ready to do arithmetic
@hattifattener
I think the problem with the water analogy is it can make people feel stupid and inadequate if they dont understand water pressure and water flow. I think that analogy was probably a lot better for a time period where practical mechanical experience was more common because tons of people were in blue collar trades.
@tubetime
@dlakelan @hattifattener @tubetime
If everyone uses the same metaphor and you don't get it you're hosed.
@dlakelan @hattifattener @tubetime I'm the toilet-drawing guy, so if you want a serious answer: my beef with the analogy is that it's too seductive and that it doesn't last long enough to make it worthwhile.
Basically, it lets people speedrun through the explanation of resistors, capacitors, and inductors, and then be *completely baffled* by transistors, transformers, and so on.
It's hard for educators to say "and now, forget everything I told you before, it's actually all fields that are in no way constrained to the wire", so many books keep going down that path for too long and invent bizarre hydraulic analogies for FETs, etc.
I know that the usual rebuttal is "all analogies are wrong, some are useful", but my rebuttal to that rebuttal is "yeah, but that one is more wrong than useful".
@lcamtuf @dlakelan @hattifattener @tubetime Just ordered it. :-) I tought physics for decades and never liked the water analogy. There are so much differences if you know a bit about flowing water.
And I think it will find it's place more likelyin the art shelf than the tech one.
@lcamtuf
I would argue that much of even those do have equivalents in the world of hydraulics. A pilot flow of hydraulic fluid can open a valve for a larger flow. (Transistor) A hydraulic jack works on a similar principle as a transformer. An automatic transmission valve body is a hydraulic printed circuit board. Yes, it doesn't work with the RF world, but it can extend further.
@tubetime That's a bipolar flush, you need to get a FET flush, just make sure it's not a JFET flush if your water is metered.
@tubetime I mean, put a hole in the bucket and you're not that far off, you even stimulate a base charge.
@tubetime That makes me think more of an SCR than a transistors. If you pull the chain (gate) water (electrons) flow from the tank (cathode, kinda) to the bowl (anode) until the tank is empty.