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This Falstad animated circuit simulation has been the best at conceptually understanding what's going on in circuits: https://falstad.com/circuit

Click on the 'Circuits' menu to see dozens of example circuits.

One issue with the hydraulic/fluid analogy is the "empty pipe" misconception - we forget or don't know that in electrical circuits, the circuit is a closed loop. An example of this misconception is that beginners sometimes think the current "wears out" as it goes along the wire. The Falstad simulation shows a line of moving dots that move faster or slower depending on the current - a little more like a train moving in a pipe - which helps counter this misconception, although it, too, isn't perfect. As a next level, I like showing animations/simulations that show the role of charge on the 'outside' of the wire in steering current flow, as well as magnetic fields surrounding the wire.


Those are exceptional. I remember gaining really nice math and physics intuition from his "applets" years ago. Yes, those started as Java applets if anyone still remembers those.

Here are math and physics ones: https://falstad.com/mathphysics.html

I like the 2D vector field one https://falstad.com/vector (2d) and the 3d one https://falstad.com/vector3d.

Antenna simulator: https://falstad.com/antenna

Waveguide is awesome too https://falstad.com/embox/guide.html. Don't forget to pick various modes in the little square at the bottom.

If Paul Falstad comes around these parts, thank you for creating and sharing those!


I'm pretty sure this is the one that I found while in undergrad physics. That diagram helped me gain a level of visual understanding that I hadn't obtained from hobby DC circuit tinkering. I remember feeling very grateful to exist during a time when an interactive web app could show me what would have taken N hours in an electronics lab to see in years prior. Many thanks Paul Falstad.


A "closed" circuit is just an open circuit plus a pump (electron pump or water pump).

Open circuits work fine if there is a powerful source of electricity (like a a radio) and a sink (like the Earth), and same for water (an icy comet crashing into a cliff, making a waterfall).

An open water circuit is full of stationary water.


Falstad is a really excellent education tool. I used it myself as an undergrad and as a tutor. Can't recommend it enough.


Cognitive load theory is unfalsifiable and wrong about many things https://edtechdev.wordpress.com/2009/11/16/cognitive-load-th...

Of course we have limits to how much we can do at once, but learning isn't like filling a bucket. Learning takes active work, effort. An analogy would be like saying 'weight lifting is easier with tiny weights' or 'don't lift too much weight.' Yes, but that's obvious, useless, and forgets the presumed goal of weight lifting, which requires putting in some effort. Similarly, you wouldn't force kids to listen to lectures about baseball or other sports and memorizing all the rules before letting them play.

Some of the other things mentioned on the poster article are false or only apply to rote, trivial learning. Remember most of this type of traditional psych research “includes participants who have no specific interest in learning the domain involved and who are also given a very short study time.”

Worked examples, like other passive learning situations, can cause an 'illusion of knowledge' - feeling like you know and understand, but not really.

Look at pre-worked answers, build rote knowledge, etc, before trying to solve problems? We learn more doing the exact opposite - see research on 'productive failure'. We learn best in context, when we have a need to learn.

Our intuitions about learning, teaching, etc, are often the exact opposite of reality. Here are just a couple of examples:

Khan Academy and the effectiveness of science videos https://youtu.be/eVtCO84MDj8

Measuring actual learning versus feeling of learning in response to being actively engaged in the classroom https://www.pnas.org/content/116/39/19251?cid=nwsltrtn&sourc...


> Worked examples, like other passive learning situations, can cause an 'illusion of knowledge' - feeling like you know and understand, but not really.

As a former educator, my experience is in opposition to this. Students who looked at worked examples and then did practice problems improved their learning rapidly but often felt like they weren't learning that much. Students who worked really hard to "figure it out" and failed often felt really intense feelings of gratification and deep understanding but, in fact, often had a worse understanding of material. I learned (as one of the studies you links indicates) that feelings of deep understanding or learning aren't very correlated with educational outcomes except insofar as they keep you motivated.

For any flaws CLT has I've never seen an alternative theory of learning that seems provide guidance that is even half as effective, both professionally and personally (I've A|B tested both myself and students a fair bit).


I read the linked blog post and had the same thoughts. The author points out that CLT has some issues and then ... suggests pedagogy based on embodied cognition instead? Come on. CLT may seem like a quasi-ad hoc explanation of certain empirical data, but at least that empirical data exists, replicates, and provides concrete guidance in the classroom. The embodied cognition literature is a mess.

Also, I think it's wrong to position CLT as opposed to active learning techniques. As long as students don't have to "discover" any essential knowledge, everything is kosher according to CLT. So e.g. peer instruction is fine (e.g. the Mazur paper under the other blog post "Evidence for Various Research-based Instructional Strategies: Countering Critiques").


Tackling problems you haven't seen before is a skill you need to practice, and probably by far the most important skill students can learn in college. Going the other way, giving them nicely packaged solutions that they then repeat robs them of this valuable practice forever, they can never go back and do those problems with a naive mind again, and there aren't that many good problems that are feasible for people to try to solve on their own like this.

Of course, since you mostly test them how good they are at repeating given solutions you wont see this difference in classes. But this difference is very apparent to how they perform after they graduate, there is a reason many people with stellar grades are horrible in practice and vice versa. If you never practiced working under conditions where you don't know exactly how to solve things then you are basically worthless at solving anything people care about.

Edit: I'd say that it is great to learn your tools that way, you don't need to understand them perfectly. But your core competence is worth investing the effort to practice solving novel problems. A physicist can learn math by just repeating solved examples, but a mathematician probably should practice solving things on his own. And solving things yourself is a lot easier in undergrad than waiting for your PHD studies etc, it is the same kind of practice just way easier since the material is easier.


>Of course, since you mostly test them how good they are at repeating given solutions you wont see this difference in classes.

Very few teachers do this in math/science/technology classes. Teachers in these subjects understand that it's the design/problem solving process that is being taught, not the particular details which are only retained on an as-needed basis.

The reality is that formalized education is rote by design. The reason many on HN were frustrated by formal education is because they are not the average student. When you are two standard deviations from the mean in ability (in either direction), school will feel like a very painful grind. Most on HN could do the entire K-12 curriculum in a fraction of the time that it takes the average student. However, the education system is designed for the average student, who by definition are the majority. Students who learn very rapidly tend to get tired of the "training wheels" which are employed in formal education. However, only once you have seen the full spectrum of student ability from the other side as an educator do you understand why they are necessary.

The real sad part of all this is that we lie to students and tell them that computer science, which is by far the most abstract and cognitively demanding subject taught in school/college, can be learned and even mastered by all. This demeans the field of computing, and often can make students feel inadequate, as they are told that everyone finds computer science very easy to understand. When faced with a challenging concept, they then immediately feel that they are stupid for not understanding it immediately.

Cognitive load theory helps with difficult subjects like CS, because it prepares the learner for intense effort. When I teach CS, the first sentence I utter to my students is: "This is going to be the hardest subject you've ever taken. Prepare yourself, and don't give up."


I don't know that we disagree entirely.

What I would say is that the thing that makes a lesson good for helping students handle unfamiliar problems well directly hamper the more concrete skill acquisition within the lesson and so you don't want to mix the two uncritically. Student outcomes are much better when teachers are deliberate about which lessons are about handling unfamiliar concepts and which are about more concrete skills like adding fractions.


> Cognitive load theory is unfalsifiable and wrong about many things

Surely these two claims are mutually exclusive?


The way I read it it means it's unfalsifiable as a general theory (that has free parameters), and wrong on many instantiations people use.

He follows that phrase with examples of more constrained theories.


i feel silly for missing that when i read it. what else do i miss, i wonder.


TerminusDB is a graph database that supports versioning https://terminusdb.com/


For me, an issue is that the most popular frameworks are created by huge companies who primarily rely on ads and tracking data, so everything requires massive/complex server-side resources, which are too expensive for someone like me who just wants to make free and open source web apps. I was hopeful about the 'unhosted' movement 10 years ago, but it kind of fizzled, as seemingly have related projects like pouchdb and solid. I'm hopeful about recent posts using sqlite in the browser and w3's storage foundation, but they are still in development, not really ready for prime time anytime soon. pwa's and the like seem to not be in much favor anymore, either.

Browser vendors (controlled by the same huge companies) blocking websql and poorly supporting things like pwa are other examples of this issue.


Has anyone made a note-taking tool (like notion/obsidian/logseq) that builds off of a computational notebook tool (like jupyter/observable/starboard)?

Mainly just needs wiki style links and backlinks and a search function.


There's Emacs's Org Mode.


nothing computational in there


That's not true. Org has a subsystem called Babel that can run code in lots of different languages, and it's pretty easy to add support for new ones.


Org Babel is the computational bit



it's a shame that "Show org source" is broken, but thanks, I'm intrigued.


I don't think this is true either. I went to one of the pages, https://orgmode.org/worg/org-contrib/babel/intro.html, clicked "Sow org source" and it took me to https://orgmode.org/worg/org-contrib/babel/intro.org.html, which does very nicely show the Org mode source code.


It's only broken on the front page, which tries to take you to https://orgmode.org.html/ when it should go to https://orgmode.org/worg/org-contrib/babel/index.org.html


If you want to see examples, look at the tutorial:

https://orgmode.org/worg/org-contrib/babel/intro.html

As for the source of that page, look at the Worg Maintenance section at https://orgmode.org/worg/

I haven't edited them yet, but I believe Worg is mostly org files on a Git repository - so you can clone it and see the source of all articles there.



mkdocs + mkdocs-material + mknotebooks


This is how Western Governors University works - they have separate instructors and evaluators. Not sure how well it works in practice, however. I have read a few complaints.


Been looking into terminusdb, an open source graph database implemented in prolog and rust. Previous discussion: https://news.ycombinator.com/item?id=22867767


One example today relates to teaching (in college). Most instructors (~75%) predominantly lecture, even though hundreds of studies have shown that increases the failure rate of students by 55% on average compared to teaching with some active learning. https://doi.org/10.1073/pnas.1319030111 We're losing hundreds of thousands of STEM major students because of that alone, disproportionately students from underrepresented groups. https://www.pnas.org/content/117/12/6476


Drupal has become more targeted to enterprise. For sites you're developing yourself, wordpress can do the same stuff as drupal now, especially with advanced custom fields (ACF). Another alternative is Statamic.


statamic is incredible...I can't recommend it enough...such a breath of fresh air


Thanks for the kind words!


Yeah, Wikipedia also has a more in-depth list: https://en.m.wikipedia.org/wiki/List_of_fallacies


Indeed a private website does not seem a great place for a master list of anything. Github or Wikipedia seem like much better places. Since it is possible to extend discussion on the validity of any member of that list, or indeed add new ones.


Github and Wikipedia are both privately-owned.

The definitions given for these "logical fallacies" are packed with rancourous comments that don't throw light on the nature of the fallacy. The names given for them are not the standard names; the classical Aristotelian fallacies are usually named in Latin (and they aren't all there).

And indeed, a lot of the so-called fallacies are not fallacies at all, because they aren't a type of faulty argument or reasoning; they're just sayings.

This is a much better list of fallacy definitions: https://www2.palomar.edu/users/bthompson/Introduction%20to%2...

It doesn't claim to be a "master list"; in fact it states on the front page that a complete list is impossible.


Agree that GitHub would be a great place for it. It's an incredible resource, and indeed (from bottom of page):

> Open Courseware | OCW |This work is dedicated to the Public Domain..

A benefit of having such a doc on GitHub would be the ease with which others could critique and contribute, potentially making the list stronger.


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