Responses to Feedback


Somewone wrote:
Two things:
The interplay between professors when one attended the other's
lecture was very entertaining.  It kept me awake and on my toes
more than once in lecture.  I found myself missing Andy's comments
and board corrections as he less frequently attended lecture.

Also, I like the way Rosakis writes his 'thetas'.  I can't
explain why.  I guess it has something to do with the difference between
capital and lower case Greek letters.  We write a lower case alpha,
beta , gamma, etc.  Why upper case Thetas and Phis??

Joe Anonymous


Ruina responds on 5/13/97:
1) I also liked attending Rosakis lectures and having him attend mine.
2) Ask him directly.  He is not too into this email thing.

Somewone wrote:
Are we being used as guinea pigs for your book?

Ruina responds on 5/13/97:
Yes. But I also like it better than any of the others available.  Thats
why we wrote it (and are improving it). Let us know how it served you
so your suffering will not have been in vain.


Somewone wrote:
Is Mahesh single? I think he is really sexy. I get really
horny in my pants when he does moment of inertia problems.
MAHESH!!!!

Ruina responds on 5/13/97:
Wait till you get your final grade and talk to HIM about this!


Somewone wrote:
What's the deal with this homework assignment due on Thursday?
I can think of a million things that I could be better using my time for than this homework.
I realize that we need to know the material, and that it will most likely be on the final.
However, I believe most of us realize this, and are responsible enough to
cover the material ourselves.  I'm curious to hear about
the method behind your madness.( at least in this case.)

Ruina responds on 5/13/97:
Your argument holds for homework for the whole semester.  The reason we have you
turn it in is to motivate you to actually DO it.  If you could learn the material
as well without doing the homework it would be silly of us to have you do the
homework in the final week OR any other time in the semester.  In the past when we
have not had people hand in this final assignment alot of students seem to let
the material go (as would they for the rest of the semester if they did not
have to turn in homework).  Actually I AGREE with you.  I don't think homework
should have to be turned in in the last week OR the rest of the semester.  This
is why we let you drop your homework grade altogether (see the course information
sheet on the grading formulae).

Somewone wrote:
How come Ano is the only TA who does HW solutions and review sessions.
The poor guy works his butt off, and does a damn good job, while the
other TA's seemingly do nothing.  I realize that they do something, but shouldn't
the responsibility by divided more evenly.  Or maybe the rest of the TA's should give Ano
some of their pay.

Ruina responds on 5/13/97:
The other TAs are doing all of the prelim and final grading.

Somewone wrote:
A course fee is ridiculous.  We pay how many thousands of dollars to take class\
es and we have to pay a course fee on top of that?
I understand paying for textbooks, but things like lab supplies should be inclu\
ded somewhere in all our money spent.

Ruina responds on 5/13/97:
The 'course fee' is to save you the trouble of having to go and buy the
lab manual, save money on the lab manual (the book store markup)
and the cost of buying software in the book store.  It does seem
like nickel and diming.     Note that with fee and all this is probably
still your cheapest class. We could drop the course fee, avoid  complaints
like this, and cost you more money.


Somewone wrote:
Professor, what's another word for pirate treasure?

Ruina responds on 5/13/97:
I don't know.

Somewone wrote:
Any hints as to what will be covered on the final?  Is it
completely comprehensive with even weight on material
covered the whole year, or will it be weighted toward stuff
covered recently?  And, would you be kind enough to enlighten
us as to what types of problems will be on the exam (ie.
weird walker problem, polar coordinates, pulleys, car probs,
etc.) how many of them there will be?  Thx dude...


Ruina responds on 5/13/97:
I got this message a little late to be useful.  I hope you got it
figured out from various information in the course handouts and so on.
Hope the exam went ok.




Someone wrote on May 3
I know when the final is but I don't know where it is. And will there be a review for the final? Thanks.

Ruina responds:
Check out CUinfo or the course WWW page for exam scheduling info. See WWW page for final week office hours and review information.


A student wrote: 5/3/97
So, if you guys (the Professors) only work about 10 hours/week for this class, what the hell do you do all day to earn this title Professor!? Sounds, like a great job to me. Copy example problems from the book and write them on the board while everybody sleeps in class, and then getting all the credit for all the TA's slave labor. Hell, a student could teach the class better than you ego-maniacs.

Ruina responds;
Let me answer your points in turn.

One gets the title professor by getting hired as a professor. Our department is unusual in that the hiring decision is based in a big way on interest and ability at teaching. However, the main business of most professors at schools like cornell is 'research'. In my case 'research' now involves the mechanics of walking, as I showed in lecture thursday. I also study things like friction and collisions. Phoebus Rosakis' research is on phase changes in solids. For the credit we get in our professional lives we both spend a disproportionately large part of our effort at teaching. Not enough to please you, perhaps, but in this research oriented environment most people would not accuse us of not trying to teach well.

It IS a pretty good job. Go to graduate school. Write a good thesis. Get people to think you are smart. And then you can have a job like this too. I wouldn't trade it in for the better paying jobs of most of my class mates. Of course we whine about it alot, but we both agree that we have a good job in a good working environment.

I don't recall copying example problems from the book in my lectures in this or any other class I have taught at Cornell, so I don't quite get that comment. For this class if I did copy from the book I don't know if one would call it copying. I don't think Rosakis has done much thoughtless pen pushing either.

It is true that we get credit for a course going well and the course doesn't go well unless the TAs, who are paid little, work hard and in a dedicated way. You can reward them by telling them that you appreciate their efforts, being attentive in section, showing an interest in the material, etc.

Some students could and will teach better than us. I used to think I could teach better than some of my profs when I was a student and it was true. I do teach better than many (but not all) of the people that taught me. I don't think I would have taught better at the time, however.

Finally, I agree that both Rosakis and I are a little self centerred.

PS: If you could put into words what you would like from us we might better please students of your ilk in future classes.


Someone wrote:
Why does Rosakis always wear black?

Ruina responds 5/1/97:
I think he thinks he looks good in black.


Someone wrote:
I heard that you can drop your lowest prelim grade in 203. Is that true?

Ruina responds:
See the course information sheet given to you on day 1. That sheet is also available from the course WWW page. If that sheet is not clear then ask again.


Someone wrote the bold things. Ruina responds in between: 4/22/97
Dear Professor Andy,

I realized a terrible thing tonight as I finished the 203 exam and glanced over the solution sheet. One cold winters night roughly 20 years ago, my parents gave birth to a moron.
You're a twin?

For some reason tonight, during the exam, it seems to have slipped my mind that we live in a THREE_DIMENSIONAL WORLD! I assumed that the masses on the ends of the dumbbell were in the form of disks, not spheres.
Big deal.

I guess it's kind of funny to think about: Young Two-Dimensional Billy, drinking his Two-Dimensional milk, thinking about becoming a big, strapping Two-Dimensional MAN. He's been working out for a few months now in a local Two-Dimensional gym. As he sits on a Two-Dimensional bench, curling a TWO-DIMENSIONAL DUMBBELL(!), he ponders what it will one day be like to flex his Two-Dimensional muscles and impress all of his Two-Dimensional girlfriends (not to mention being able to throw a Two-Dimensional football much further than are able any of his Two-Dimensional friends on the Two-Dimensional football team). He'll drive a Two-Dimensional sports car, earn a Two-Dimensional paycheck at a Two-Dimensional burger joint, and stun his Two-Dimensional parents with an outstanding Two-Dimensional SAT score.
Thats the way most simple mechanics is done. The two dimensional girlfriend doesn't sound especially fun, but the rest works out ok.

Anyway, I was hoping you might see your way to giving me credit for the first problem on the exam (only if I did it correctly with disks, of course), dispite my being a Two-Dimensional Idiot. I redid it three times tonight until I got it right. I guess I'd rather not feel like it was a wasted effort.
This is a small error, and probably a common one. Any reasonable grader would not zap you much for this.

We had intended to shade those disks to make them look more sphere like but at 3 this morning I got tired of touching up the exam and didn't do it. So it is MY fault. About 44.3 years ago on a cold winter night my parents gave birth to an idiot!

If you can't help me, I'll understand, but I thought I ought to give it a try.
No special consideration but I think you are not in big trouble. Most of us make much bigger mistakes than that reasonably often.


Someone wrote the bold things. Ruina responds in between: 4/18/97

So there's an annoying girl in lecture now, eh?
If she's in lecture she's probably not my daughter's age and thus a woman. Right?

I wouldn't know because I haven't been to lecture in about 3 weeks.
I've been missing a few myself recently.

I wonder what chapter we're in now.
The ones about circular motion. The later parts. I think thats chapters 5 and 6.

Is that Rosakis guy still teaching?
Yes.

He's pretty cool.
I think so too.

I wonder who would win in a fight between Ruina and Rosakis.
Where from comes this pre-occupation with fights? A few years ago in front of a large class in Kimball B11 my foot got caught under the front desk a wierd way and I fell flat on my face in the middle of some explanation. It was very funny ha ha. Then, in the student comments at the end of the semester, some guy (I assume it was a guy), something like you in mindset it seems, wrote something like: "I wonder who would win a fight between Ruina and Professor or TA X. Probably X cause Ruina would take himself out, like the time he did in lecture ...".

On the other hand, when I was in graduate school we used to imagine competitions between professors where they had to race to solve partial differential equations (We called them boundary value problems). We imagined the slow but inexorable Jim Rice would steadily plow his way through using dimensional analysis and scaling principles while the neurotic and hyper Jack Pipkin would jump hither and thither writing and erasing various series expansions and complex integrals.

I suppose our curiosity sort of parallels yours.

Ruina might have a size advantage, but I think he's getting old
Fractionally, I am getting old slower than you, wise guy. In absolute terms, neglecting relativistic effects, we are all getting old at the same rate. But my decline in fitness probably comes more from lifestyle than time, however. Satchel Page won lots of ball games when he was older than me.

and is past his prime.
I was past my prime for fighting when I was about 7. My mom was always proud of her non-violent (passive aggressive) nerdy son who at age 5 answered a challenge for a fight with 'no, lets do math problems instead'. I'd still rather deal with 'what's nine take away five' than a punch in the nose.

He'd be too slow to react to Rosakis' jabs.
I'd be too stunned - why would he jab me! He loves me and I love him. Why would he jab?

I'd bet he'd get his ass kicked.
I hope so.

I think you should give us the solutions before we do the homework every week.
Its a reasonable proposal. We've discussed it.

I don't feel like thinking for myself and doing it right now.
Then don't do it. Do something you like. Maybe kick your friends around or something.


A student wrote:
I have a complaint about grading policy concerning free-body diagrams. i fully understand that, in order to solve many dynamics problems, being able to draw a good fbd is necessary, and that this is something you are trying to teach. i think, however, that this is being over-emphasized in grading at times, and that there are cases in which a solution is simple enough to be to be found with out the use of a guiding fbd. i will admit that requiring free body diagrams is a good way to train students to get into the habit of utilizing them for when they encounter more difficult problems, in the same way that you might roll up a newspaper and tap a dog on the backside for chewing up your slippers, so he doesn't do the same to your favorite pair of rockports or birkenstocks. but kicking him square in the rear is only going to piss him off, and having experienced this first-hand, i tell you i don't like it. i don't wish to detract from this by making it personal, but just as an example, i lost six points for lack of an fbd on question two of the first prelim, and i felt this to be a little much, seeing as it didn't reflect any lack of knowledge on my part about the question or answer, only on how lazy i am. it is my belief that this should have amounted to only a point, perhaps two. i have to admit, however, that kicking this dog has made a fast learner out of me, and that's the last time i'll forget to draw an fbd, whether i think i need it or not. just so this isn't completely a negative feedback, i enjoy the lectures given by both professors, as well as their antics in the classroom which prove to be highly entertaining. i think that mariano garcia is one of the best TAs that i have encountered at cornell, and i think he should get a raise. he's quick to help answer any questions i have, he explains solutions in a way that i find easy to comprehend, and he's very patient and understands exactly where it is that i am having difficulty. thanks.

Ruina responds (4/14/97):
I am sympathetic to your complaint. When I do simple problems I don't always draw a FBD. I don't even write anything down. Its all in my head.

BUT...

Even if you do a simple problem without a DRAWING the FBD neatly on paper, you will be missing a great opportunity to communicate your reasoning to a skeptical, unknowing, or naive reader. The FBD is a key part of the communication process in mechanics. By being so strict on the grading we probably cause some students to get grades which under estimate their knowledge.

But this is the price we pay to get people to learn things in the manner we want. I think, on balance we are doing about the right thing.

We give plenty of warning that we will be strict about these things, so its not like a suprise is it? If so, maybe we should give more clear warning.

So I feel for your complaint but am not sure you would really have us do something different. Or would you?

Thanks for the nice feedback.


Someone wrote in: Why is that girl so annoying?
That girl is soooo annoying; I'll bet she's the one who complained about bad language in lecture. She's soooo annoying that I spend most of lecture thinking of how to get back at her for being so annoying. She's soooo annoying in fact, that I have trouble paying attention to lectures.
The annoying girl is making it very hard for me to learn in 203.
I'll bet a lot of people would be doing a lot better on the prelims if it weren't for that annoying girl. Can you do something about that annoying girl?
Thank you.

ps. Could you also convince the MAE 225 professors to have an anonymous e-mail page? That class is desperately in need of honest student input.
TAM 203 is an excellently taught and well structured class.
Thanks.

Ruina responds: 4/11/97
Assuming you are not talking about my daugher the person in question is probably called, in modern language, a woman. What woman I have no idea. How could she mess people up on the prelims? Let me know who it is and how she is annoying to you and I might be able to do something, you never know. (I won't post her name here.) [ That she can push your buttons so effectively might be a sign that you are doomed to be her friend. Something like a family member who just doesn't happen to be biologically related. ]

Tell me what you want sent anonymously to the 225 professors and I will forward it. As a starter I have forwarded your comment to Michel Yves Louge and Marjolein C.H. Van Der Meulen (the listed teachers). I doubt they have the inclination to set up an anonymous form like this one since it takes a bit of effort and gives a fairly small return. I have made several unsuccesful attempts to convince CIT to support anonymous email for just this purpose.
CIT said it is against their principles (that you can send anonymous snailmail, anonymous campus mail, anonymous FAXes, leave anonymous notes, and make anonymous phone calls doesn't seem to have any strength with them as an analogy). You could always send a note. Most faculty DO want feedback (even if we seem defensive at times). Most of us have many years left in our teaching carreers and would be all the happier if we could please our clientelle better.

Thanks for your comment about 203, but flattery will get you nowhere. What could we do better?


Someone wrote to 203 anonymous feedback:
I have a question. Who is this Rudra Pratap person? Is he someone that Professor Ruina has locked up in a back room and is forced to write textbooks such as "Getting Started with Matlab" and "Dynamics", or does he even exist? I would like to see this Pratap person to dispell my belief that Pratap is not a person at all but just a huge Matlab file, Pratap.m , that Professor Ruina put together to automatically write textbooks.

Ruina responds:
The virtual reality simulation rudra_pratap.m has been under development for the past 30 years or so in a few countries and languages. It contains several high-level pedagogical routines which led to it being rated higher as a teacher than any real teacher in M&AE last year. It also has high level logic and argumentation routines that convinced me

  1. That with it as a partner we could write a 'better' Dynamics text book.
  2. That the best way to get rid of computer illiteracy amongst engineers (the inability to use computers usefully for short engineering calculations) was to try to get MATLAB spread through the engineering school. I have faithfully been running this routine for years, as assigned by rudra_pratap.m.

The rp simulation has some defects however in that it has wasted a lot of clock cycles 1) trying to work with me on the 'better' dynamics book, and 2) outputting a MATLAB book that does make it easier for students to 'Get started with Matlab'.

The multi giga-bite routine rudra_pratap.m is being FTP'd from Bangolore India to Ithaca, New York on May 9, 1997 if the various protocols don't interupt transfer. It is currently programmed to teach virtual MAE 326 this summer.

You will recognize its friendly user interface. It is programmed to entertain you at a coffee/tea/beer/soda dispensory should you have data concerning any of its output (ie comments on his books). Submit such requests to pratap@mecheng.iisc.ernet.in before May 8 and rp28@cornell.edu therafter.

By the way, the rudra_pratap.m is too big (in the non-corporal sense) to have been written by any one group of programmers. My attempts to modify a few of its small subroutines have largely been unsuccesful, fortunately.


Someone wrote:
I hate 203

Ruina responds: 4/6/97
In terms of your long term knowledge it is probably more important for us to get you to like the class than to teach accurately and completely. We don't always yield to this educational philosophy but we do pay some attention to it.

What do you hate? Is there something that could be done about it? Things within our abilities, things beyond our abilities?

As they say in my daughter's pre-school in response to incompletely articulated expressions of discontent: 'Use your words."


Anonymous feedback from someone:
It seems like the TA's do most of the class work. Do they get paid?

Ruina responds: 4/3/97
The TAs are paid to work 15 hours a week. This gives them about $10,000/yr to live on plus their tuition. In fact they work more like 18-20 hours per week for this class. They do do much of the work of grading, running labs, writing solutions, proctoring exams, sections, office hours, as do they in most large courses at Cornell.

Faculty are also supposed to spend something like 'half time' on their 'teaching' which includes a variety of teaching and advising like tasks. Over the semester this class alone will take me an average of something over 10 hours per week.

There are twice as many TAs as faculty each working nearly twice as hard as the faculty. So the TAs do something like 80% of the net work.

Given that they work so hard for so little pay any appreciation you express to them will certainly be appreciated. They are all trying to do a good job and trying to learn how to do better. The personal reward of an occassional comment from a student is worth alot.


Someone wrote:
What the hell kind of #deleted# complains about a professor using naughty words in class? Someone tell this #deleted# to shut the #deleted# up.

Someone else wrote:
In response to the anonymous comment about Professor Rosakis's swearing in class- I find that it makes the environment much more relaxed, since most of us probably do swear on ocassion. It makes Professor Rosakis seem to be a real person, someone I can relate to, rather than an intimidating professor. It would be a shame if any professor had to change who they are to satisfy the overcritical opinions of one overly moral student. Additionaly, I can assure you that plenty "professional" people do swear.

Ruina responds:
Informal language related to digestion, sex, and eternal suffering or requests to minimize use of such --- we all have our sensitive sides. Precise technical description or informal chat --- we have different tastes in what we like to hear.

As professional teachers trying to do our profession well we try to find ways to accomodate the heterogeneity of our audience.

Feedback helps.

Any other opinions about other topics that require balancing and compromise (Theory vs Examples, Examples vs Demos, Hard vs Easy, Details vs more material, more material vs more depth, breadth of exposure vs competence at less, basic skill development vs new material, etc.)?


An anonymous student wrote:
I would like to request that Professor Rosakis be more careful in his choice of words he uses in class. I find profanity in a lecture setting distracting and offensive, not to mention extremely unprofessional. I would enjoy class much more if this could be taken care of. Thanks.

Ruina resonds on 3/26/97:
This is a matter of taste. Certainly your opinion is not unique, but there are others who like a more informal approach. At any rate, your suggestion has been heard and Professor Rosakis now knows that at least one student is sensitive to his choice of words.

Rosakis responds:
Certainly I do not wish to distract or offend anybody. I appreciate your bringing this issue up and will take it into account, although I cannot guarantee that you will find everything I say unoffensive in \ the future. Your comment about extreme unprofessionalism, however, can also be considered offensive.


An anonymous student wrote:
Am I allowed to date the professor?

Ruina responds on 3/4/97:
By Cornell law the same reasonable policies hold for TAs as faculty, I believe. Cautions about older possibly married men are appropriate, however. And, as most readers are probably thinking, you're kidding right?


An anonymous student wrote on 2/28/97:
Am I allowed to date my TA?

Uncle Andy responds on 2/28/97:
I have not read the rules letter by letter so I could be wrong, but I think there is no Cornell law that forbids this. There are rules about how such relations are not allowed to be tangled with the grading etc. In the common ethic, felt rather strongly by many people, it is improper to be romantically involved until after the semester ends. Forgetting legal and ethical issues, it is certainly the easier way to go. But there is a long tradition of student-teacher intamacies (I know two men who are married to their former teachers, and a former grad student in this department married her pet student.)

But, ... at least two of the TAs are involved in long term relationships, presumable monogomous (but what do I know). So that might cut into your fantasies some.


An anonymous student wrote on 2/25/97:
Comments = Does your new "safer" bungy system work or are you still dropping your in-laws?

Prof Ruina responds 2/27/97:
As you have picked out, the prelim question number 3 was a pretty good sketch of the system I built last summer that dropped both my wife (broken rope) and her father (slipped knot). It is claimed to be safer than jumping down from a high height. But my system is mow only safer than it was in that I use a stronger rope and check my knots more. I haven't rigged it up since last summer. Unfortunately I have no good video footage of it in fun mode, or in the mode of horizontal oscillations like in the prelim.

Maybe in the spring time I will hook it up again.


An anonymous student wrote on 2/25/97:
Comments = could you put the new sylabus on this page?

Prof Ruina responds on 2/26/97:
Sorry to be so slow on getting out the syllabus. We hope to get to it by the time March lectures begin. Thanks for the nagging.


An anonymous student wrote:
I noticed some errors in the book. On the cover, it says "An Introduction to Dynamics", but on the title page it \ says "Introduction to Dynamics". Which is the correct title? Also, in the preface on page vii, second paragraph, Paul Tipler's name has one\ "p".
Good luck!

Prof. Ruina Responds:
Thanks for your feedback. We are in desparate need of help with improving the book. We will buy you coffee or lunch if you have a few minutes worth of comments or ideas. About specifics: I don't know what the title will be. I think the 'an' sounds pretentious (sp?). About Paul Tripppler, I am a very bad speller, errors like that can only be found by people like you (whoever you are).
Thanks for the good wishes.