DISCLAIMER: This was not intended for publication as much as to clarify my own thoughts. I don't intend it to represent my current view, nor does it probably represent my past view, as it was written as an emotional document. Of course, this doesn't make learning something from it impossible, so that's why I put it here for you! january 20th I guess 1993 What I have found to be the most valuable for me as a Physics student and in helping Physics students: A professor enters the room, and he stands at the board and teaches physics. A student enters the room and sits down and wants to learn physics from the teacher. If this relationship continues as it is -a teacher teaching physics and students learning from the teacher- then a number of questions must be asked in order to determine how those interactions should take place. If these questions are not asked and answered, then the students will find themselves in the unfortunate predicament of not caring, not understanding, and approaching nothing. Correspondingly, the teacher will be constantly wondering why the students are so dense, so apathetic, and have no idea what they should be learning- and he may even be questioning whether he knows where he is attempting to guide them. Some questions I would ask are: What are the goals of taking the physics class? This question could be answered in the following ways: to get a 'physics mind' so that when we are presented with a physical problem, we instinctually know which pieces of information are salient, and which questions to ask; to be able to repeat convincingly the historical laws (meaning Newton's laws, the laws of thermodynamics, optics, etc-- at this point I remember a bit of a story by Feynman of a trip to Brazil, I think, where he was talking to a graduate student in physics. They were at the ocean, and Feynman asked the student 'do you know this and such a law' and the student repeated the law very convincingly, and then he looked out at the ocean and asked something like 'when the sun hits the water like this, why does that happen,' an application of the law the student had repeated, and he stood there bewildered.) ; to know which historical laws apply to which situations; to be able to do operations using historical laws and naming the laws as you perform the operation; to understand what a function is; to be able to write a lab report so that we can learn to be scientifically convincing by straightforward explanation. I myself am concerned most with having the instinctually correct approach to solving problems. Second on my list would be knowing what a function is, if I did not. Other people have other priorities perhaps, but that is mine. I suppose I seek mainly to enjoy what I am doing and what I enjoy most is realizing fast ways to solve problems. I suppose many people would say that is immature. But what I am interested in from physics is understanding things at a level so that I can solve specific problems I am interested in. For example, this summer my father suggested that the rain was so heavy 1% of the air must be full of drops, and I proceeded to show in numerous ways the implications of this 1% theory- amogn others, that our car would be going considerably slower due to the mass of air it would have to move (if it were not completely underwater first) and there would be 1 cm falling every .1 second (a .1 second being a estimate of the time it would take a 1cm sheet of water to fall to the place of the next 1cm sheet, (1 m) at 10 m/s. Another example is that I wondered once how you could compute the power of an automobile, and my dad and I thought up all different ways to compute it. A good cook knows physics, and a good auto mechanic knows physics. A good cook doesn't need to have a book of recipes to have a recipe and can fix things for next time, and a good cook does that on the basis of physics. The same is true for an auto mechanic-- in fact, every driver should be able to conceptualize a c-v joint, and if they can't and I were the teacher, I would bring in an old c-v joint, and tell them to go find it on the car. hell, maybe physics classes should be when some students go to the junkyard, one person runs and takes some part off a car and then everybody else tries to get one, too. Who can figure out what makes the cylinders fire at different times? One of my dad's friends told him once that when he was joung and lived near a junkyard every time a new car came into the yard, they would sneak in, take all the oil out and run it to find out what part broke first. If I'm in a physics class and at the end of it I couldn't think up any way to measure the power of a car, that is a problem, and if I couldn't estimate the per cent water content of the air, that is a problem. On the other hand, I realize you can only learn so much and some people have been in a physics class their whole lives. Still, I am altogether convinced that learning historical laws is in and of itself not worthwhile. The question is, does it contribute to people's instincts of problem-solving? The teacher walks in and begins by introducing Newton's laws. Then he writes equations on the board for each one. Then he says the kind of problem each law applies to, and, if the students are lucky, he gives one example. The process goes from most abstract to least abstract, to an actual situation. Later, the student attempts to do some homework. At first he reads the problem. Then he thinks to himself, shit, I've never seen this done, and looks at his notes, and tries to remember what the teacher did in class. So he remembers that the teacher gave a lecture about Newton's first law, and so he says to himself, ok, Newton's first law, and then looks at his notes and says ok, this is the equation for newton's first law, but god damn, i have got no idea if this is the right equation or not, and how I can use it if it is. So he gets help, and can do the homework. If the help is good, he understands what he is doing; if the help is bad, he is clueless. Sometimes the help has to work against the teacher to get the ideas of Newton's law out of someone's head to allow something else in. If the help is not good, one month later the student could not do a similair problem, does not know Newton's law, and is confused. If the help is good, one month later the student can still do the operation becuase he used it and saw why he was using it, and it worked, and he probably forgot Newton's first law. So, as far as I'm concerned, the student was attempting to do the problem backwards. This is the way I approach a problem: 1encounter the problem and instinctually know the answerr else, if I don't know the answer, I will 2instinctually know how to find the answer else, if not, I will 3thinkabout the logic behind the situation based on my experience and attempt to logically discover a rule else, I will 4read the section review to see if I can quickly get the answer, or look at the sample problems 5and last, I would make rules about all physics problems (for example, Newton's laws)- yet, physics students are far too often given a BACKWARDS example of how to go about physics by their teachers: 5 tell all about generalizations 4,3 show generalized equations while discussing the logic of the situation (2 omitted) 1, (sometimes) do sample problems. So of course the physics students are not going to have any idea how to approach problems, and they are going to begin to write silly newtonian law equations on their pages before realizing what the problem is. This has been a section to hopefully show how unsuccessfull it has been thus far in physics classes to choose methods other than direct problem-solving for learnign problem-solving. Still, some peopl will say that those other things are important too, and that is their right. I would not want to know them if I were in the class, but that is tough luck for me perhaps. As far as labs are concerned, I think that as long as they are presented in a way that follows this form: solv this problem: why does a rocket not go as high as the equivalent energy of burning its fuel? or: propose five ways to measure the power of a car. How reliable a thermometer can you make with things you find around the physics lab? I would prefer very much if students did labs of their choice entirely with teachers as resources, suggesting the topics and available to help. Labs like the thermo lab where the answer the teachers were expecting was illogical, and not related to any thermo the students had been learning are SO FAR FROM REASONABLY REQUIRABLE. Specific heat at constant length? Nobody understood specific heat anyhow, not at all, not at constant volume, not at constant pressure- at constant LENGTH? there wasn't a word about elastics in any thermo we did- jesus, all we did was GASES. and having this crap reduce to quadratic equations? eEven if that is true, such confusion as that would create is enough to destroy governments- in fact, I think the Soviet Union may have fallen due to misuse of constant length. Propose a thermodynamic cycle for this machine? What kind of an insane person would use this to generate power of any kind? And if there are some, I wish you'd said. People so infrequently learn things when they are not interested that you have to let them do whatever they want, if they get themselves interested in something. This business of students doing only the experiments and not the deciding of what experiment to perform to find something out seems inane. Students should have a question and seek to answer it, or they should have an idea and seek to try it. Attempting to cover the requirements of four pages of questions and two pages of comments and five lectures is BULLSHIT. What has to happen is that they have to be able to figure out for themselves the answers. So maybe you need to tell them how you would go about finding something out. And if all the students want to, they can all do that experiment at first, but that is their bad choice if they were smart enough to do something more creative, or their good choice if they're too scared to know what to do. I think the profs here have one problem:: that they have been brainwashed into hampshire missilusion that the reason why something happens in physics can have a long explanation with a generalization as opposed to simple experience through exercising instinct on actual problems. Hampshire profs somehow aren't supposed to give tests. I don't know when that bull started, but it has made this moral that problems are not important to spend time on, but that justifications are. problems come first, else they will never be understood. Originally there were real exams intended by FPat or whoever wrote that book. Ah, enough for tonight. Unfortanely I think I will have to rewrite thiks else hurt herb.