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Andromeda321
2005-Jan-28, 04:48 AM
Ok guys, I need to rant, and the topic of the rant is my E&M class. Now I was really looking forward to this one because of all my radio junkie work previously and got really excited about thinking hey, I'll finally understand what exactly's going on in my radios etc. But right now we're three weeks into it and I'm seriously worried that I'm going to fail, which is a first for me (in the sense that I'll work my hardest and still do so). And I feel so stupid right now you have no idea.
To start off with, the prof sucks. He's a guy who talks in monotone for 50 minutes without tucking in his shirt assuming the class has already taken multivariate during lecture when about half of us are still in calc II (including me). To top it off the guy has no freakin' office hours claiming instead you can email him when you want an appointment/ go to recitation. Well sorry Professor but I have orchestra during your precious recitation and I don't know a week in advance what questions I'll have to ask you!!! ](*,)
Oddly enough in the homeworks I can do the problems relying on math (Gauss's Law, integrating to find potential, etc) well enough and it's the ones that rely heavily on concepts that fly over my head. And to top it all off I keep thinking how I'm an astronomy/physics major, for God's sake, so why the heck can't I do this?!? Am I just stupid? Really, I've began thinking that crawling into a corner and crying is a viable option more then once already...
Ok, end of rant now. Sorry if anyone's ear fell off.

Brady Yoon
2005-Jan-28, 05:05 AM
Hey don't worry! Astrophysics is arguably the hardest major there is. The thing that counts is you're learning alot.

Celestial Mechanic
2005-Jan-28, 05:06 AM
What textbook(s) are you using for E&M? Some of the regular posters here might be able to suggest others to look at.

My undergraduate E&M was by Lorain and Corson, my graduate text the second edition of Jackson. This was almost 25 years ago, however. I think the Jackson book is in a third edition now, for example. I also used a book by A. O. Barut.

If calculus is still being taught the traditional way, Calc I would be differential calculus, Calc II would be integral calculus, and Calc III multivariate calculus with multiple integrals, partial derivatives, and maybe some differential equations thrown in. The most important thing you would need for use with E&M is a bit of vector calculus, so that you can understand gradients, divergences and curls. It's very difficult to do E&M without them!

Perhaps if you mentioned a few of the concepts that fly over your head some of us may be able to suggest some reading material. Hang in there!

beck0311
2005-Jan-28, 05:13 AM
If it makes you feel better, half of the electrical engineers I know hated E&M too. I had the same problem that you do, the math used is more appropriate to people who have had multivariate calculus, but I was taking it at the same time, as the course prerequisites stated.

Just keep plugging away, and you will probably do fine. I cannot tell you if upper division physics is any better, but the Physics III course I took (Optics and Modern Physics) was a lot easier than E&M.

We used Halliday Resnick (sp?) which I am led to believe is fairly standard, but I never really liked too much.

papageno
2005-Jan-28, 10:26 AM
When I had E&M in my undergraduate years, it was terrible.
The lecturer was some sort of clown, who was not able to explain things his life depended on it (by the way, he became the director of the Gran Sasso National Laboratory).
We hardly paid attention to his lectures.
Thankfully, the texbook (written by him and somebody else, IIRC) was fairly understandable (it used an nearly historical approach).
What really helped me, was the exercise book and my arguments about E&M with a colleague.
But we had the advantage of having done already vector calculus.

My advice: read the first chapters of Feynam's Lectures of Physics, Vol. 2. These explain a few things about vector calculus, which should be helpful.

Electromagnetism seems huge as a field (and it is when you look at the applications), but it is founded on few principles.
Once you get to Maxwell's equations, everything you learned before should "click" into place.

jumbo
2005-Jan-28, 11:02 AM
My E&M experience wasnt great either. The lecturer had hundreds of pages of notes that he copied from his papers to the blackboard. The thing that kept us awake was taking bets on what his first sentence would be and how much he looked like Mr Burns from the simpsons.(I nevere one the bets...my guesses of @release the hounds' 'eeeeexcelent' and 'Young man theres no need to feel down i said young man....' never came up!)

We spent the first half of the course furiously scribbling down the reams of note leaving us no time to think about the content. Until we found in the library was a copy of an E&M text that was word for word identical to the notes. Our scribling became check the book out of the library and learn for ourselves. Thus we bypassed the lecture takes out book->copies book to paper in dodgy hand wrinting->copies handwritten version to board->we copy down version form the board and down have time to think chain. Saved a lot of cramp in my hand and understanding shot up.

Sheki
2005-Jan-28, 12:41 PM
You say you are "three weeks in"?

Well, let me suggest a blasphemy: drop the course. If it is too late for that, then "withdraw" from the course. I am not sure what the rules are like where you are, but back when (and where) I did my undergrad you could "drop" a course (no penalty - didn't even show up on the transcript) within the first couple weeks if you wanted. Later, if things got really scary but it was past the "drop deadline" you could still "withdraw". A withdrawal would show up on the transcript (as a "w" grade for the course) but did not affect the GPA calculation.

I withdrew from a course once (Calc II), because the prof was horrible, and I wasn't a good enough student to compensate. I was completely lost in that class - confused into a state I had previously not thought possible. I took the course under a different prof later and got an A+ (it was actually my favourite class that semester!)

That withdrawal was the best academic decision I ever made - replaced a certain F with a W. Of course a W doesn't look great on the transcript, but it is pretty ambiguous. No one can tell by looking at the transcript why you withdrew... (and if anyone ever asked (say a potential employer) you can just say that you took it for fun as an elective but it turned out that the time requirements cut into other coursework too much).

Of course, depending on other factors, that one withdrawal might really screw-up your timeline for completing the degree - but if you would fail the course anyway...what the heck!

Sheki

Fortis
2005-Jan-28, 12:44 PM
We used Grant (http://www.amazon.com/exec/obidos/tg/detail/-/0471322466/qid=1106916042/sr=8-4/ref=sr_8_xs_ap_i4_xgl14/102-1340325-9190515?v=glance&s=books&n=507846) from the Manchester Physics Series, which I recall was pretty good.

It's strange, but the thing that I found useful was to abstract everything. I found it easier than what I had been doing, which was to imagine problems constructed from tarnished brass spheres with bits of wires dangling off heading towards an earth, etc. :)

swansont
2005-Jan-28, 12:53 PM
I used Introduction to Electrodynamics by Griffiths as an undergraduate, and thought it was pretty good. Jackson, of course, in Grad school.

Normandy6644
2005-Jan-28, 01:18 PM
We used Purcell last semester, which no one really liked. I agree too that the Feynman lectures are a great help for understanding the concepts and things like that. The hardest part I found about E&M was the complete incompatibility of the lectures with the homework problems. Most of us could understand the lectures just fine, then have NO IDEA what we were supposed to do for a homework problem!! There is an REA book on electromagnetism that is entirely solved problems, so that might help too.

pumpkinpie
2005-Jan-28, 01:39 PM
I used Introduction to Electrodynamics by Griffiths as an undergraduate, and thought it was pretty good. Jackson, of course, in Grad school.

Totally agree. Griffiths is very clear. Get it as a supplement. And Jackson was to hard for me, even in grad school!

sts60
2005-Jan-28, 07:30 PM
Andromeda,

chin up! You're in a tough curriculum, but you can do it - however, Seki's idea of seeing if there's an opportunity to take it with a better instructor is a good one... And don't be afraid to ask for help. (Scratches head, jogs creaky neurons for EM memories... :-k )

You're smart, but you're not the first smart person to feel this way. We're pulling for you. =D> \:D/ :D =D>

And I third the Griffiths suggestion. It's very clear and readable.

Lurker
2005-Jan-28, 07:49 PM
Andromeda,

Its a really hard subject. If I read your post right, he is assuming knowledge on your part that you don't even have yet. Believe me this stuff is ugly when you do have a all the background. I have to agree with the idea to drop the course. Hey, I dropped a course or two and still ended up with a PhD (and I'm not even smart). You might want to consider rounding out your background and try again, there is no shame in that.

On the subject of your professor... welcome to the dark underside of the academic world. He's a lousy instructor and that's not your fault. If you had a more complete background you might be able to figure this stuff out inspite of him. This should be unnecessary, but often true. #-o

There are good professors out there and a few will have voices that still guide you long after they are gone. So hang in...

Andromeda321
2005-Jan-28, 09:03 PM
Hey all, thanks for the support, you've made me feel better. :)
Well first off despite the suggestions of dropping the course the fact of the matter is I can't really because I want to graduate in four years and I can't do that should I drop (still a frosh so it's allowed). Unless I wanted to cop out and be an engineer/ humanities major instead of taking physics until I die (engineers only need a year's worth of physics). But for what it's worth I run with a crowd much better then me in academia (the ones who set the curve) and they're out of it too. So all in all we're currently in the "we might not get it but everyone doesn't get it even more" mentality... fun times.
Thanks for the book suggestions though, I will certainly look into them! We're currently using the Halliday-Resnik book which isn't too bad but doesn't explain how the examples connect to the main ideas in my opinion...

tlbs101
2005-Jan-28, 11:21 PM
When I took EM I was a junior. I can't believe your advisor even considered putting you in that class in your Freshman year!

If there is any possible way to postpone this class, I would recommend you do -- notwithstanding the quality of the prof. teaching the class.

Normandy6644
2005-Jan-29, 12:25 AM
When I took EM I was a junior. I can't believe your advisor even considered putting you in that class in your Freshman year!

If there is any possible way to postpone this class, I would recommend you do -- notwithstanding the quality of the prof. teaching the class.

I think there are two classes. I know in my school we have the intro E&M and then the advanced one. The difference is mainly mathematical sophistication, but there certainly is a difference!

Tobin Dax
2005-Jan-29, 02:48 AM
Andromeda, everything is hard the first time you see it. Am I correct in assuming that this is a basic E&M class, with an advanced one (or two) coming later on? If so, don't fret too much. I hated my basic physics w/calc series. It gets better as you get higher up. If this prof won't help you, and you can't drop the class (which you shouldn't if it's the basic series), is there someone else who can help? A general TA/help room? Even doing your homework in a group is a good thing. That's something that I started way too late. If you're not in a study group now, I strongly suggest that you find/start one. Plus, if you can't get to recitation, maybe someone else in your group can. :)

Oh, what text are you using? (I don't see the answer to that, yet.)

AT
2005-Jan-29, 02:53 AM
I took the Advanced E&M (not inclulding QED, mostly) last term, and, while it was really hard, the professor was awsome. I think its just one of those classes that you have to hope is well-taught.

Tobin Dax
2005-Jan-29, 02:58 AM
After poking around, it looks like you're most likely taking Phys 122 or 124 (I'd guess 124?). Like I said, don't fret the intro level too much. Getting a B or two won't kill you, especially in your first year. You'll be fine. Just do the best you can, find a study group to figure out the homework with, and find other help if you need to (maybe the 122 TA or someone similar would be willing to help you if they're not busy during their office hours).

swansont
2005-Jan-29, 03:20 PM
We're currently using the Halliday-Resnik book which isn't too bad but doesn't explain how the examples connect to the main ideas in my opinion...

So this would be the E&M part of the general physics sequence, right? Unfortunately, in some schools this is one of the "sink or swim" classes, used to cull people from the curriculum. I don't know if that's the case with your class, but I recall a lot of over-stressed prospective engineering students when I was a TA, because they needed a certain GPA to get into the engineering sequence. (I remember being told by one such student the grade I had given on the first lab was unacceptibly low - like it was my fault, and that the solution of working harder and paying more attention to the lab instructons wasn't an option. :o )

Unfortunately, the intro physics class is typically the prerequisite for everything, so you may have to just keep with it. If you can find a few other students with whom to study you might be able to learn more.

Normandy6644
2005-Jan-29, 04:09 PM
Is the class curved? That would certainly help. A lot of people in my class last semester had a hard time, but we still ended up with decent grades because of how the actual scores were distributed. I'm still not totally sure how it works, but I know that it does!

Donnie B.
2005-Jan-30, 09:42 PM
Hey all, thanks for the support, you've made me feel better. :)
Well first off despite the suggestions of dropping the course the fact of the matter is I can't really because I want to graduate in four years and I can't do that should I drop (still a frosh so it's allowed). Unless I wanted to cop out and be an engineer/ humanities major instead of taking physics until I die (engineers only need a year's worth of physics). But for what it's worth I run with a crowd much better then me in academia (the ones who set the curve) and they're out of it too. So all in all we're currently in the "we might not get it but everyone doesn't get it even more" mentality... fun times.
Thanks for the book suggestions though, I will certainly look into them! We're currently using the Halliday-Resnik book which isn't too bad but doesn't explain how the examples connect to the main ideas in my opinion...
Have you considered forming a study group with others in your predicament (hopefully including some who've completed the advanced Calculus)? Sometimes it helps to bash ideas around among several heads.

Normandy6644
2005-Jan-31, 03:21 AM
Hey all, thanks for the support, you've made me feel better. :)
Well first off despite the suggestions of dropping the course the fact of the matter is I can't really because I want to graduate in four years and I can't do that should I drop (still a frosh so it's allowed). Unless I wanted to cop out and be an engineer/ humanities major instead of taking physics until I die (engineers only need a year's worth of physics). But for what it's worth I run with a crowd much better then me in academia (the ones who set the curve) and they're out of it too. So all in all we're currently in the "we might not get it but everyone doesn't get it even more" mentality... fun times.
Thanks for the book suggestions though, I will certainly look into them! We're currently using the Halliday-Resnik book which isn't too bad but doesn't explain how the examples connect to the main ideas in my opinion...
Have you considered forming a study group with others in your predicament (hopefully including some who've completed the advanced Calculus)? Sometimes it helps to bash ideas around among several heads.

Yeah, that's how I do it. It works really well too.

Andromeda321
2005-Jan-31, 04:47 AM
Yep, because if I didn't I know for a fact I'd be failing this term! :wink: