<p>I often hear engineering majors mention how in your freshman calculus based engineering classes you have to derive the formulae used by yourself. Could an engineering major enlighten me on what exactly this entails? For example, I'm in AP physics B right now, so its still an algebra based class, but our teacher derives every equation we use. Which of the following two examples is most accurate by what is meant: 1) I have the equation P = IV and the question asks for the resistance. I also know that V = IR, so I can substitute that in for V and get P = I^2R and find the answers. 2) When beginning the electricity chapters, our teacher showed us how to derive E = (kQ)/r^2. He did this by drawing a diagram, placing a point charge at an infinite distance, then moving it closer and closer and finished by setting up an equation using integration. </p>
<p>Basically, are engineering majors expected to set up pictures/equations and use integration and such to derive a formula when little past knowledge has been had?</p>
<p>It is not just freshman classes - this is a common method of teaching the theory at ALL levels of engineering education. And yes, the basic process is to take whatever initial conditions are provided, along with previously established equations, and through some type of mathematical operations produce the needed formula.</p>
<p>The rule of thumb I’d apply is that if something is an axiom or definition, you don’t have to justify it. If something is a major theorem for the class, you don’t have to derive it. If something is something that was derived for one problem on the homework, you should derive it.</p>
<p>Alright that’s not too bad. I was worried I’d have to do something along the lines of my second example without any or little prior knowledge of the material. Thanks!</p>
<p>Contrary to what you might hear, they do actually want you to pass - you will not be given assignments that are genuinely beyond the ability of the class, and will always have the resources to complete them. The only real issue is whether or not you actually use them.</p>
<p>Yeah I became interested in engineering at the beginning of my sophomore year and since then until a month or two ago (I’m a senior now), I heard nothing but horrible horrible things about engineering and how only hyper intelligent super geniuses can pass it and I was quite honestly scared out of my mind. As you can see, I’ve joined CC and a few other websites, asked and read some questions, and my fears have been dropping a significant amount. From what I’ve gathered, if I put in the work I’ll be fine.</p>
<p>It is not as much about intelligence as it is about discipline and PATIENCE. You have to have a mindset to do 3/4 of problem…find out that you totally messed up and start over again from scratch.</p>
<p>I’m taking Calculus based Physics 2 at a community college right now. I’ve made dozens of integrals similar to what your professor did in the second example, and we’re only half way through the semester. You get used to it, it’s not a big deal.</p>
<p>You don’t need to by a hyper intelligent super genius, or even a regular genius. It’s just study and practice like everything else in life.</p>
<p>You get used to the symbol pushing after a couple of math/science/engineering classes. What can make engineering hard is when your professor puts a problem type on a test that you’ve never seen before, or one that expands on an idea you already know. Then again, that’s kind of what engineering is all about, usually without the hour time limit though :-p</p>
<p>I don’t know about other universities, but at mine there’s been no explicit demand to derive equations. Often times the professor will introduce a topic by deriving it from a simpler equation or one that we’ve covered in a previous chapter, but after that it’s mostly just applications of the equations. They might say “you don’t have to memorize the equation, you just have to be able to derive it”, which means memorize the equation. From what I’ve heard, though, organic chemistry is one of the only classes that requires excessive memorization. Besides that, you’ll probably have seen examples similar to the test/exam questions and you’ll know how to solve them.</p>
<p>Thanks for all of the replies everyone - they’re helping a lot. da6onet, could you give me an example of putting a question on a test that wasn’t in the chapter? My current calculus teacher this year does that with about 1-2 questions on each test. Those few are definitely more challenging but I’m getting used to it and it’s obviously good practice.</p>
<p>On the expansion of ideas:
I remember a hydrostatics problem from calc where plates of simple shapes were submerged in a liquid. The example used in lecture was with a semicircular plate, the selected homework problem used a trapezoid shaped plate, but the one on the test was a triangle (of course in hindsight, it is in the book, just not assigned). On the test I had to quickly figure out the relationship between the width of my dx rectangle and the base of the triangle. Just geometry/algebra, but it was the time crunch that made me remember it as trickier.
Another one from that class was finding the volume of a solid obtained by rotating about the x-axis, the region between y=1/(x^2) and y=0 to the right of x=1, if it converges. This was an easier one, but I remember it because I thought it was an interesting combination of concepts.</p>
<p>Example of something not covered:
More recently from my circuits class. We hadn’t talked much about power dissipation/development after the first day of class or even seen a problem with a variable resistor in lecture, on a quiz, or homework. Guess what shows up on the first test? Power questions as a part of every question, one involving a variable resistor on a Thevenin equivalent circuit that was already tedious enough to find because it had three dependent sources. I mean, yes, power is just another formula, and variable resistors aren’t that bad, but I hadn’t done the non-assigned textbook problems dealing with them because I hadn’t seen them emphasized (wasn’t alone in that regard). That kind of blindside really upsets me because I normally would have done a couple of the non-assigned problems (same with the hydrostatics problem in calc). I still got 100 on the test (same with the calc tests), so I shouldn’t complain.</p>
<p>I think what bugs me the most about these kinds of problems is that they are, in the big scheme of things, actually easy. It’s just hard to see it sometimes when you’re taking a timed test.</p>
<p>I know exactly what you mean when you say in hindsight the problems are extremely easily. We’re actually on circuits right now and sometimes we’ll get a homework problem with about 10 detours and an absurd amount of capacitors etc. The whole class comes in the next day and no one could solve it. Then our teacher does it in 30 seconds on the board and I always wonder how I didn’t think to do what he did. </p>
<p>Speaking of stressing about the time limit, one of my parent’s friend’s kids went to engineering school (I can’t recall the school) and a few of his teacher gave unlimited time during all tests so students wouldn’t perform poorly due to stress. The school wasn’t super prestigious but it wasn’t a joke either. Too bad other schools don’t do that haha. Thanks a bunch for taking the time to help me out, by the way. I appreciate it.</p>