5 ms·

Yeah, this kind of idea is why I’m dead against using things like the hydraulic analogy in early EE for anyone who is ever going to want to do more than the ‘ho

Yeah, this kind of idea is why I’m dead against using things like the hydraulic analogy in early EE for anyone who is ever going to want to do more than the ‘hook some things up to an Arduino’ (or probably ESP32 these days) kind of level electronics. The gaps between the analogy and the real world actually make it harder to understand the fundamentals and just confuse people when you get to a deeper level understanding. It requires more unlearning than is worth it for the slight benefit of making the concepts slightly more intuitive to understand at the beginning.

junon 1y ago
Once I ditched the hydraulic analogy and really tried to internalize charge, current, voltage, etc. is when I finally started to understand why the hydraulic analogy "works" but only for people who already understand electricity. Electricity behaves in many ways just like water (just at a significantly faster time scale) but I don't think it actually helped me learn how it all worked to start with.
- r_lee 1y ago
  This is a common problem in all fields IMO. It's easy for many to fall into the "It's like X" but it only makes sense if you already have the information needed in your head to connect the dots Which is why I also don't generally like analogies and the kind
- foobarchu 1y ago
  This reminds me a lot of the car analogy that gets used to (poorly) teach object oriented programming.
marcosdumay 1y ago
Hum... The hydraulic analogy is for school kids to learn what electricity is. If you are creating circuits to hook into an arduino, you should have moved from it already.
- not_that_d 1y ago
  I feel insulted.
  - marcosdumay 1y ago
    Instead, if you still use it, just drop it because it's probably holding you back. And if you managed to move ahead in hard mode, you shouldn't feel insulted.
- lukan 1y ago
  I believe school kids should be already creating circuits and hooking them up to arduinos.
- kevin_thibedeau 1y ago
  It is a flawed analogy but it behaves like a fluid more than most realize: https://youtu.be/2AXv49dDQJw?feature=shared&t=1248 https://youtu.be/2AXv49dDQJw?feature=shared&t=1248
  - marcosdumay 1y ago
    Electricity behaves a lot like a fluid. But not much like water or air, so there's little point in using it as an intuitive analogy.
therealcamino 1y ago
I had a CS professor as an undergrad who would teach a couple of advanced seminars in his own research area. His approach to those simplifications was to announce, "I'm going to lie to you now, but just go with it and I promise that later we're going to learn the real truth." I liked that as a compromise, to make some practical progress, but not to mistake the simplification for full understanding. (And he wasn't rigid about it -- if somebody would ask a deeper question he'd happily answer it to some level and then get on with his plan.)
bee_rider 1y ago
The hydraulic analogy always sort of confused me because, like, fluid mechanics are real complicated. So, I always had this gut feeling question of like, can we actually end up with a hydraulic analogy that is exactly as complicated and electricity and magnetism? If we push the analogy beyond what is intended? Is it an analogy or are both models expressions of some underlying model of potentials and flows, and we happen to have more hands-on experience with water?
- antod 1y ago
  Yeah. As I mentioned in another comment, as someone who studied Civil Engineering (ages ago) maybe most EEs never learn enough hydraulics to know the analogy probably goes further than they realize - ie much further than just kids level stuff. Voltage drops across components or look a like head drops across pipe fittings. Losses along a pipe are similar to wires. Head and flow rate are very similar to voltage and current across multiple paths. Kirchoff can apply to both etc. Many of the quantities have direct parallels and derive from each other in similar ways. Obviously there are limits. But my middling DC circuit knowledge helped a lot when learning hydraulics from a mathematical engineering perspective.
antod 1y ago
Heh, I used electrical circuit analogies when learning hydraulics for pipe networks in Civil Engineering. I struggled much less than the other students who didn't know any basic electrical stuff from physics classes.

junon 1y ago

Once I ditched the hydraulic analogy and really tried to internalize charge, current, voltage, etc. is when I finally started to understand why the hydraulic analogy "works" but only for people who already understand electricity. Electricity behaves in many ways just like water (just at a significantly faster time scale) but I don't think it actually helped me learn how it all worked to start with.

r_lee 1y ago
This is a common problem in all fields IMO. It's easy for many to fall into the "It's like X" but it only makes sense if you already have the information needed in your head to connect the dots Which is why I also don't generally like analogies and the kind
foobarchu 1y ago
This reminds me a lot of the car analogy that gets used to (poorly) teach object oriented programming.

marcosdumay 1y ago

Hum... The hydraulic analogy is for school kids to learn what electricity is. If you are creating circuits to hook into an arduino, you should have moved from it already.

not_that_d 1y ago
I feel insulted.
- marcosdumay 1y ago
  Instead, if you still use it, just drop it because it's probably holding you back. And if you managed to move ahead in hard mode, you shouldn't feel insulted.
lukan 1y ago
I believe school kids should be already creating circuits and hooking them up to arduinos.
kevin_thibedeau 1y ago
It is a flawed analogy but it behaves like a fluid more than most realize: https://youtu.be/2AXv49dDQJw?feature=shared&t=1248 https://youtu.be/2AXv49dDQJw?feature=shared&t=1248
- marcosdumay 1y ago
  Electricity behaves a lot like a fluid. But not much like water or air, so there's little point in using it as an intuitive analogy.

therealcamino 1y ago

I had a CS professor as an undergrad who would teach a couple of advanced seminars in his own research area. His approach to those simplifications was to announce, "I'm going to lie to you now, but just go with it and I promise that later we're going to learn the real truth." I liked that as a compromise, to make some practical progress, but not to mistake the simplification for full understanding. (And he wasn't rigid about it -- if somebody would ask a deeper question he'd happily answer it to some level and then get on with his plan.)

bee_rider 1y ago

The hydraulic analogy always sort of confused me because, like, fluid mechanics are real complicated. So, I always had this gut feeling question of like, can we actually end up with a hydraulic analogy that is exactly as complicated and electricity and magnetism? If we push the analogy beyond what is intended? Is it an analogy or are both models expressions of some underlying model of potentials and flows, and we happen to have more hands-on experience with water?

antod 1y ago
Yeah. As I mentioned in another comment, as someone who studied Civil Engineering (ages ago) maybe most EEs never learn enough hydraulics to know the analogy probably goes further than they realize - ie much further than just kids level stuff. Voltage drops across components or look a like head drops across pipe fittings. Losses along a pipe are similar to wires. Head and flow rate are very similar to voltage and current across multiple paths. Kirchoff can apply to both etc. Many of the quantities have direct parallels and derive from each other in similar ways. Obviously there are limits. But my middling DC circuit knowledge helped a lot when learning hydraulics from a mathematical engineering perspective.

antod 1y ago

Heh, I used electrical circuit analogies when learning hydraulics for pipe networks in Civil Engineering. I struggled much less than the other students who didn't know any basic electrical stuff from physics classes.