5 ms·
>Early classes on circuits in EE will usually take shortcuts using known circuit structures and simplified models. Might just be me, but I found it all clicked
by carlmr 1y ago
>Early classes on circuits in EE will usually take shortcuts using known circuit structures and simplified models.
Might just be me, but I found it all clicked when we started learning the fundamentals underneath these abstractions. For me it was harder in the first classes because it's about memorizing poorly understood concepts, my brain prefers logically deriving complex concepts as a learning method.
- stephen_g 1y agoYeah, 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 agoOnce 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 agoThis 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 agoThis reminds me a lot of the car analogy that gets used to (poorly) teach object oriented programming.
- marcosdumay 1y agoHum... 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 agoI feel insulted.
- marcosdumay 1y agoInstead, 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 agoI believe school kids should be already creating circuits and hooking them up to arduinos.
- kevin_thibedeau 1y agoIt 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 agoElectricity 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 agoI 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 agoThe 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 agoYeah. 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 agoHeh, 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.
- sevensor 1y agoMy biggest criticism of EE pedagogy is that it tends to proceed from abstractions and then derive the whole world. This makes it a bit of a slog for a lot of students. I’d like to see an application-first approach that builds up principles from observed behavior. Like, measure the slip in an induction motor and then work out what’s going on there, instead of deriving motors from Maxwell’s equations.
- korse 1y agoDon't forget, Faraday hated math.
- carlmr 1y agoThat's a good point, too, I had a bunch of abstractions without applications in my head.
- wetwater 1y agoIts interestine, when you say abstractions. Could you explain what you mean by abstractions in this context and what do you mean by the underlying fundamentals.
- carlmr 1y agoOne example would be resonant circuits. Ok great you can build resonant circuits, but what for? The fundamentals to understand frequency responses came later in signals and systems. The application came much later when I learned about electric motors, which basically behave like low pass filters (resonant circuits) which enables us to use PWM to generate sine shaped current curves by switching the input voltage on and off. The voltage signal is smoothed by the LPF circuit that is the motors windings. I think it would have helped me if we talked about the motor or other examples first, and then did some math to show how the resonant behavior can be useful.
- sevensor 1y agoIt’s crazy that VFDs work! You have to have a really good ground though, or you get arcing through the bearings.