sophiecentaur said:
My point is that learning formulae off by heart represents (or at least it should) a very small part of a subject like Physics so why not just get down and learn them.
It depends on the educational process, but I was taught with the "fire hose" theory of physics, in which they take a fire hose and blast you with data and see what you can pick up.
A typical problem in a physics test would require you to use a dozen formulae. You were allowed to have one letter sized "cheat sheet" and typically people wrote all of the formula in extremely tiny font so that you could pack as much information onto that one sheet as possible. And you needed it.
The important things that they were trying to teach were
1) process knowledge - i.e. writing down the chain rule wasn't useful. The question was whether you could use it, and
2) selection knowledge - If I give you 100 formula, can you very, very quickly figure out which are the 10 that you need
Also, putting together the cheat sheet was educational. For example, when I did rotational acceleration, velocity, and distance, the formulas are all the linear one times r. Now you can waste space by writing each formula separately or you use shorthand to write down that they were part of the same concept.
Part of the rationale for the firehose theory of physics education is that if they blast you with data, your brain will start to absorb the equations at a deep and subconscious level. For example, today, if you give me a picture of a box on an inclined hill, I'll immediately see the vector components, because those things have been imprinted at a subconscious level. I don't even have to think about it.
If a student just can't be bothered to learn the small number of formulae involved in, say, what we used to call statics and dynamics, in A level - or the very few formulae used in simple circuit theory - then I would say they haven't shown much commitment. It's along the lines of a concert pianist needing the names of the notes to be marked on the keyboard.
But the way that I was taught, it wasn't a small number of formula. For example, you have a dynamics problem. But *ha*. we put into parabolic coordinates so you have to figure out how all of the formula work in the new coordinate system
As far as simple circuits. I remember that one exam problem that I had about twenty different circuit elements with transistors. Your job was to very rapidly analyze the circuit so that you could break things down to where your formula was useful.
Or you have a simple circuit. V=IR great! Except that the wire was 3000 miles long, and you had to figure out how the speed of light would effect your calculations. At this point you had to pull in Maxwell's equations.
The problems I had were *deliberately* set up so that you couldn't get anywhere with rote memory.
Also, there was a masochistic element to this. I ended up loving getting beat up by test problems.
I can't think of an instance when actually knowing something would not help in solving a problem. When would using a printed list help you better?
It depends on the aspect of "knowing". Here is something to try. Try reading this paragraph. Only for each word, say out each letter. Hard. Now for each word, read every *other* letter backwards. Your mind will be so taxed, that you aren't going to notice what I'm actually saying.
The way that I was taught physics, the idea was to make the formula disappear. Trying to memorize the formula was adding a mental tax that got in the way of what was actually being taught.
The two go together and the whole is a lot greater than the sum of the parts. Just read the huge number of questions that we read on this forum, clearly written by actual Physics students, which show that they just have no recall of some of the most basic relationships - or they have possibly even rejected the importance of them.
It's very hard to figure out what is going on here. Also, I should point out that the firehose theory of physics works pretty well for me. It would be a disaster for a lot of people.
Also forums are hard because I don't think that you can teach physics with one question / one answer, which is one of the issues with online education.
The other thing is that a lot of people are able to be fluent speakers of a language without consciously knowing the grammar of said language. Memorizing grammar is one way of learning a language, but it's not the only way, and it's not hard to find examples of people that whiz through TOEFL without being able to carry on a conversation in English.
Are they ever going to get a grasp with that approach? Formulae are only concise statements of models, after all, and isn't that what Science is all about?
Don't know. One thing that makes this difficult is what is the point of a physics class? If it's to teach physics to people that want to be physicists, then you have a totally different approach than if there is some other goal.