Show Your Work

[Brant Gaede]

I will never post on your site again. I would prefer not to have anything further to do with you or to communicate with you again. Quite frankly, your weakness and double standards disgust me.

Makes me think of the saying in Kölsch (Cologne dialect): "Wat kümmert mich ming Jeschwätz von jestern?" ('I couldn't care less about my gibberish from yesterday').

So is Phil going to apologize to the site owners for his rants against them? How about explaining why he has changed his mind about posting here? It seems not.

Please look at this video.

--Brant

[Brant Gaede]

I will never post on your site again. I would prefer not to have anything further to do with you or to communicate with you again. Quite frankly, your weakness and double standards disgust me.

Makes me think of the saying in Kölsch (Cologne dialect): "Wat kümmert mich ming Jeschwätz von jestern?" ('I couldn't care less about my gibberish from yesterday').

So is Phil going to apologize to the site owners for his rants against them? How about explaining why he has changed his mind about posting here? It seems not.

Please look at this video.

--Brant

[Brant Gaede]

I will never post on your site again. I would prefer not to have anything further to do with you or to communicate with you again. Quite frankly, your weakness and double standards disgust me.

Makes me think of the saying in Kölsch (Cologne dialect): "Wat kümmert mich ming Jeschwätz von jestern?" ('I couldn't care less about my gibberish from yesterday').

So is Phil going to apologize to the site owners for his rants against them? How about explaining why he has changed his mind about posting here? It seems not.

Please look at this video.

--Brant

[Philip Coates]

Mike, nice answer [post 23]: I'm going to have to carefully think through each of your points to make sure I understand and agree.

> on the topic of seeing the physics in action, it's definitely very important! I had a terrific physics professor who always had about ten 'toys' out for every lecture. I had an awful physics teacher in high school, though. Maybe one or two demonstrations for a whole year. Pretty hard to learn physics without a large number of guided observations.

My high school physics course left me having learned virtually next to nothing. It was supposed to be an attempt to induce by experiment, to have labs, to have demonstrations for every step in physics. That can be a very easy teaching method to screw up. The textbook was PSSC Physics and the teacher was horrendous.

I have a no doubt exaggerated recollection that Mr. Whoopsydaisy never got a single experiment or demo or lab equipment to work properly**. At a certain point I just tuned out and that made me have to play catchup in a fast-paced college/program where I was a physics minor (math major).

**when I had some experience teaching in the sciences, I found out that having the right equipment and practicing with it beforehand and not having things break down or embarrassingly fail to demonstrate the principles involved is one of the big challenges for a teacher...which is why so few of them seem to do it.

Right now the reason for this thread and all these questions (and another thread I did on physics last year?) is that I'm trying to go back and relearn physics -thoroughly- over the course of a year or more: not skipping any steps this time and no "hand waving", doing pretty much every problem in the back of each chapter. I want to make sure I understand each principle. I bought a very early edition (1948!) of the Sears and Zemansky text (University Physics) we used in college. The only thing I don't like about it so far is that it says "it can be shown" a lot with regard to physical laws and formulas. It's also quite terse and often has only one hard problem to illustrate an entire subtopic, but I then do a thought experiment to extend it.

Two things I -do- like in an intro survey text: (i) it uses pounds and feet in the problems, allowing me to visualize the real world situations and grasp their magnitude [i can always translate to metric system if I were to become a professional]. (ii) it starts with statics not with kinematics -- force and vector problems in equilibrium, of the kind we are discussing here. Most modern textbooks start with motion - velocity, acceleration, gravity, etc.

Are you a college student majoring in engineering or science? A working chemical engineer?

Edited August 9, 2011 by Philip Coates

[Brant Gaede]

Hi, Phil. Apologized to Michael yet?

--Brant

[william.scherk]

I'm going to have to carefully think through each of your points to make sure I understand and agree.

Phil, you know I like you, and you should know I am glad to have lots and lots of folks 'back' on OL, and so am glad to have you back . . . but in my opinion you should give serious thought to answering a question that lurks in several minds.

When you stopped posting earlier this year, you wrote (indicating MSK), "I will never post on your site again."

Now you are back posting.

The questions lurking will not go away, but will reemerge in different forms over time, I think. So, my friendly advice to you is to address the disjuncture between the 'never' post and the present physics thread. Just do it. Just ask yourself, "Hmmm, big guy, why are you posting on OL again after storming off?" And then answer. Each time you are again addressed with what is a pretty basic question, and each time that you ignore the question, the disjuncture becomes deeper and deeper.

So, cut to the chase and please just answer the question in a way that satisfies you.

I doubt very much MSK will enter and question you about this, since he doesn't really give a shit one way or the other what you do, but would it not seem strange to you if the positions were reversed, if MSK had stormed off your forum?

[Rich Engle]

I'm going to have to carefully think through each of your points to make sure I understand and agree.

Phil, you know I like you, and you should know I am glad to have lots and lots of folks 'back' on OL, and so am glad to have you back . . . but in my opinion you should give serious thought to answering a question that lurks in several minds.

When you stopped posting earlier this year, you wrote (indicating MSK), "I will never post on your site again."

Now you are back posting.

The questions lurking will not go away, but will reemerge in different forms over time, I think. So, my friendly advice to you is to address the disjuncture between the 'never' post and the present physics thread. Just do it. Just ask yourself, "Hmmm, big guy, why are you posting on OL again after storming off?" And then answer. Each time you are again addressed with what is a pretty basic question, and each time that you ignore the question, the disjuncture becomes deeper and deeper.

So, cut to the chase and please just answer the question in a way that satisfies you.

I doubt very much MSK will enter and question you about this, since he doesn't really give a shit one way or the other what you do, but would it not seem strange to you if the positions were reversed, if MSK had stormed off your forum?

Phil transcends all boundaries. He swoops down like the Roman God that he is. Don't press him for explanations, or you will be smitten. Well, more likely pounded into a catatonic condition of some sort. There are no human laws for this, unless Phil<tm> says so. Be grateful for the Presence of Phil<tm>. How dare you question him. You should be asking him what he likes--various types of sweetmeats, fruit, and so on--then send it to him.

You should be saying: "Welcome back, O Sultan of Shifting Rules."

Phil has died, and Phil Has Risen. With a physics problem. Fuck yeah.

I urge you all to visit the Temple of Phil that I created here. Remember his funeral? It was magnificent--but only as much as we could manage.

I, for one, am joyous and worshipful. Remember this Golden Moment, courtesy of Peter Taylor?

Phil was told,Phil, you *are* a hypocrite.

and Phil replied:

Up yours, cunt.

rde

You want fries with that, Phil?

Edited August 9, 2011 by Rich Engle

[Rich Engle]

Something is rotten in the state of Philmark<tm>:

Phil has chosen to change my avatar over to his spectral image shot. He sent me an email:

Do not smite me. I accuse thee witch. Remember the Salem trials, motherfucker--I hanged hard on that one, and I can do that again, fuck-face: that was the 1600's. I kicked ass then, and you can only imagine what technology (I call it Philnology, as will my masses) has done at my bequest since then. I will serve Thee math problems. I will correct Thine thoughts. I will foul your wenches (the rest breaks off to a series of symbols, weird audio files of chanting, and some kind of offer to join the Church of the Sub-Genius; I asked those guys about it and they so far haven't found anything--ED)

Apparently It has taken over a number of servers. This is some really funky shit, folks. Hide your women and chillun's.

rde

On his way to Wally World to get some shotgun shells and a few things to barricade the quarters.

[Philip Coates]

[Selene]

<<<<Phil's formal lesson on answering ND's question.

[Brant Gaede]

<<<<Phil's formal lesson on answering ND's question.

The real, basic problem with Phil is his intrinsic elitism. Nobody else matters intellectually. Ayn Rand seemed to have the same problem, with much more reason, but in many circumstances she still had a lot of grace--a very big and complicated person. Unlike Phil, she never went out of her way to display her brains. OL is quite out of the way for basic problems in complucatable physics.

--Brant

[Rich Engle]

<<<<Phil's formal lesson on answering ND's question.

The real, basic problem with Phil is his intrinsic elitism. Nobody else matters intellectually. Ayn Rand seemed to have the same problem, with much more reason, but in many circumstances she still had a lot of grace--a very big and complicated person. Unlike Phil, she never went out of her way to display her brains. OL is quite out of the way for basic problems in complucatable physics.

--Brant

He needs a good mouthpiece to get out of this one and I have just the guy:

[Mike Hansen]

Right now the reason for this thread and all these questions (and another thread I did on physics last year?) is that I'm trying to go back and relearn physics -thoroughly- over the course of a year or more: not skipping any steps this time and no "hand waving", doing pretty much every problem in the back of each chapter. I want to make sure I understand each principle. I bought a very early edition (1948!) of the Sears and Zemansky text (University Physics) we used in college. The only thing I don't like about it so far is that it says "it can be shown" a lot with regard to physical laws and formulas. It's also quite terse and often has only one hard problem to illustrate an entire subtopic, but I then do a thought experiment to extend it.

Two things I -do- like in an intro survey text: (i) it uses pounds and feet in the problems, allowing me to visualize the real world situations and grasp their magnitude [i can always translate to metric system if I were to become a professional]. (ii) it starts with statics not with kinematics -- force and vector problems in equilibrium, of the kind we are discussing here. Most modern textbooks start with motion - velocity, acceleration, gravity, etc.

Are you a college student majoring in engineering or science? A working chemical engineer?

I am a junior in chemical engineering, at the University of Utah.

Those times when the book says "it can be shown", give google a try. A lot of science/math/engineering professors post their notes online (usually you'll see them as the first search results), and I've found wikipedia to be fairly useful and very accurate with regards to scientific matters. Wikipedia is particularly nice in that you can often get those derivations that a lot of textbooks lack.

By the time you get to fluid mechanics, I guarantee that you will begin to despise the monstrosity that is the English unit system. In statics, things aren't too bad, but I have a feeling you'll start working in metrics and then converting to English. It's not just the fact that it is base-10. It's the conversion factors required in English units. Pound-force versus pound-mass is only the beginning!

Mike

[BaalChatzaf]

. Pound-force versus pound-mass is only the beginning!

Mike

Slug it out (that is a pun, by the way).

Ba'al Chatzaf

[Rich Engle]

Dammit I can't find the Phil Shrine. MSK? Anyone? Where is that damn thing? That was some of my better work.

rde

Crumbling Mayan Ruins

[Philip Coates]

> By the time you get to fluid mechanics [Mike H, post 38]

Mike, I'm not going to go in the direction of fluid mechanics. I'm just trying to rebuild / extend my knowledge of basic physics and a little engineering. At this point statics, although I expect to work thru the rest of the curriculum.

> Those times when the book says "it can be shown", give google a try...

One problem I'm having with physics "101" (I have a stack of textbooks and am getting the impression they may all be this way)is its jumping from topic to topic. Sears and Zemansky is terse. It wants to cover the waterfront, a vast subject requiring 49 chapters in a single year. It spends a minimal amount of time on each topic -- condensing a long historical development into a few pages, asserting some principles and equations have been shown, then giving a brief problem set - not always with 'meaty' examples.

What I want to see is how 'statics' works with more complex, real world structures: buildings and important massive structures human beings build which are vital to civilization and economies and which have to be sturdy enough. Here are the five things I particuarly want to *fully* understand the mechanics of: 1) house, 2) skyscraper, 3) tunnel, 4) jet airplane, 5) rocket ship.

Sophisticated. I don't want to just read about the force equations or moments or center of gravity for a single weight suspended from a single fucking cable and hanging off a single fucking strut!

QUESTION: When you studied this subject do remember working through more realistic and complex cases of one or more of types 1-5 I list above?

If it's not in the freshman physics curriculum, any idea what kind of textbook do I need to go onto Amazon and shop for that adequately deals with these? I have an intro to mech engrg book, but it stops well short of those. I've read for years about how the invention of the arch, the flying buttress, etc. 'transfers' force and stress to the supporting pillars. But none of these intro physics books (at least the ones I own) seem to bother telling us how to trace all the relevant forces.

The examples are too damn simple and 'cooked' to allow me to get a satisfying sense that I understand mechanics in the complex real world. And that's what I want to have before I feel I have some -mastery- of forces and moments and how to fully apply them in chapters 2 and 3 and move on to work, energy, impulse, momentum, rotation, and other topics. I really don't like to jump from subtopic to subtopic like they seem to do in phys 101 -- like a mindless cookbook with problem sets -- without having fully enough *integrated* each one.

My reason for studying the subject again in the first place is so I can really understand physics (and a bit of engineering) in a way I didn't the first time around. (Not just plugging stuff into equations.)

I *specifically* want to understand the forces involved in the structural integrity (and in the latter cases, resistance to a lot of strong forces or stresses) of a simple house, skyscraper, tunnel, plane, spaceship.

Edited August 12, 2011 by Philip Coates

[Mike Hansen]

Sounds like trusses would interest you quite a bit.

This website should help: http://emweb.unl.edu/negahban/em223/note12/note12.htm

When I took my Statics and Strengths of Materials course, we did a few "real" problems, but things can get really complicated really quickly.

Also sounds like Shear & Bending Moment Diagrams would intrigue you. This website is very dense and not easy but should be interesting: http://ocw.mit.edu/courses/materials-science-and-engineering/3-11-mechanics-of-materials-fall-1999/modules/statics.pdf

I looked up "Structural Analysis" on Amazon.com. There's a book by R.C. Hibbeler under that title. I've had two of his textbooks in the past and he is terrific. (Maybe go for an older edition, though, since the newer ones are fairly expensive)

Mike

[Rich Engle]

Sounds like trusses would interest you quite a bit.

That is, without doubt, the funniest line all week. Pure economy!

Good piece of work, raht thayer.

rde

Ham and Feet Sandwich Award!

Edited August 12, 2011 by Rich Engle

[Rich Engle]

Phil is saying he ate a whole fucking bunch of Taco Bell<tm> and is getting ready to clog the entire Florida sewage system. Mad Ninja power! Phil:

"What I'm saying is that 23,000 lbs (of tension or compression) to support 2000 lbs makes no sense and is not what happens in the real world. "

That is why being in the Longshoremens' Union is critically important. To your well-being, I mean. Did you ever meet guys like Unibrow Dante? If you haven't, be joyous about it. The Big P continues:

"And I could make the numbers much worse:"

That, I never doubted.

rde

Edited August 12, 2011 by Rich Engle

[Philip Coates]

Thanks, Mike! Those are very helpful tips. Here's what an Amazon reader says bout the Structural Analysis book you mentioned: "This book provides an excellent introduction to structural analysis. The photos, illustrations, and attention to details are unparalleled by any other structures book. The illustrations show realistic structures, not meaningless stick diagrams." On the strength of that and your comments, I just ordered the 4th Edition from Amazon.

The only caveat might be that the book blurb says its applications are to trusses, beams, and frames - which may be too narrow or too specialized if I want to understand the whole structure of a house, skyscraper, tunnel or airplane. I'm wondering if I ought to also get a book on civil engineering to cover other aspects of how these applications work?

(I'm starting to look thru Amazon at the blurbs and reader comments on civil engineering, since it concerns many of the structures I'm interested in...but again the level of discussion would be crucial: not too stick figurish and superficial and not too specialized in terms of only one aspect of the real world problem.)

[Selene]

Phil is saying he ate a whole fucking bunch of Taco Bell<tm> and is getting ready to clog the entire Florida sewage system. Mad Ninja power! Phil:

"What I'm saying is that 23,000 lbs (of tension or compression) to support 2000 lbs makes no sense and is not what happens in the real world. "

That is why being in the Longshoremens' Union is critically important. To your well-being, I mean. Did you ever meet guys like Unibrow Dante? If you haven't, be joyous about it. The Big P continues:

"And I could make the numbers much worse:"

That, I never doubted.

rde

Build it and she will come????

[Philip Coates]

Mike, In your engineering studies, did you have a -general- course in engineering as opposed to a lot of courses in physics and a lot of courses in types of engineering or important topics in engineering(structural analysis, materials, statics)?

The reason I ask is I wanted to pick up a general textbook with a title like "Engineering", but searching under that name on Amazon returns nothing which seems to have that as its broad (yet thorough) subject. Everything seems to be a subdivision or specialized like mechanical engineering. Or popularizations like Florman and Petroski. Or handbooks of formulas. . . Very surprising and disappointing!

(A couple years ago when my interest in engineering re-awakened, I bought the Saeed Moaveni book, a 300+ page paperback edition, but at that length -- even though it seems good on introducing general principles and issues -- it is 'light' on meaty real world examples. Like skyscrapers and dams and airplanes and highways.)

I've noticed in many fields that finding the right level of study - the right level of abstraction and general principles and level of detail, well-developed examples - is a problem. It's the age of the narrow specialist. I wonder if this is true in your field as well?

Actually, I should address my question to anyone else who majored in a technical field: (a) Did your field have a similar "gap" problem? No good survey textbooks or courses, plunging too quickly into technical detail, jumping from topic to topic? (B) And/or too little satisfying exploration of a rich or complex 'case' or problem set so that you felt: Aha! Now I understand why and how those laws and principles and methods really work in the real world?

Edited August 14, 2011 by Philip Coates

[Jonathan]

I've noticed in many fields that finding the right level of study - the right level of abstraction and general principles and level of detail, well-developed examples - is a problem. It's the age of the narrow specialist. I wonder if this is true in your field as well?

The "right level of study" as defined by what standard? People generally write textbooks geared toward people who are seriously interested in a particular subject or discipline, and not for people like you who are never going to actually use the knowledge and only want to learn exactly what they want to learn, and no more and no less, and who want to complain during the entire learning process that all of the textbooks in the world haven't been tailored to their lazy mindset. There's nothing wrong with the textbooks, Phil. The problem is your short attention span and resistance to work -- your wish for everything to be made easy for you by others, and to then move on to a shallow understanding of the next subject that momentarily interests you.

Actually, I should address my question to anyone else who majored in a technical field: (a) Did your field have a similar "gap" problem? No good survey textbooks or courses, plunging too quickly into technical detail, jumping from topic to topic? (And/or too little satisfying exploration of a rich or complex 'case' or problem set so that you felt: Aha! Now I understand why and how those laws and principles and methods really work in the real world?

I've never had any of the problems that you mention in any field that I was seriously interested in. You may want to restrict yourself to the "For Dummies" section at your local library or bookstore. They're written for lazy dabblers like you.

J

[Brant Gaede]

The best teachers are true experts who enjoy imparting their knowledge to people who really want to understand things to their roots. Since I'm not a physicist I can only guess that Richard Feynman was such a teacher. I've known one expert physicist who hated teaching. I think it was impatience with people who couldn't get up to his speed right away.

--Brant

[Guyau]

Hi Phil (#47),

My formal education in Mechanical Engineering (B.S. 1983) was atypical in that I had already earned a degree in Physics (B.S. 1971). I did not have any course or text in engineering overall or in mechanical engineering overall (e.g.).That was no problem, and in my case it would have been just slowing me up.

Well, actually there was one course, in senior year, pertaining to engineering profession, but it was not technical; its emphasis was on professional ethics. The assignment for the first three weeks of class was to read The Fountainhead. Cool course, taught by a Ph.D. who had worked in commercial industry and in legal cases.

My courses and texts in undergraduate engineering school were specialized down to this level:

Kinematics and Dynamics of Machines

Design of Machine Elements

Fundamentals of Mechanical Design

Introduction to the Mechanics of Solids

Engineering Mechanics of Materials

Vibration Analysis

Introduction to Fluid Mechanics

Fundamentals of Classical Thermodynamics

Basic Heat Transfer

Thermal Environmental Engineering

(i.e., refrigeration; heating and cooling)

Design of Thermal Systems

Process Engineering

Electricity, Electronics, and Electromagnetism

Measurement Systems

It was fun for me to see how Newton’s mechanics gets used in engineering mechanics and fluid dynamics. It was also fun to learn classical thermodynamics. In my physics degree, I had learned the basis of thermodynamics in statistical mechanics, but didn’t have much idea of what thermodynamics itself was. Engineering rounded out understanding of the physical world I had gotten from physics.

At the level of undergraduate work, we did not have specialization within mechanical engineering. Further learning and specialization (and shifts to other divisions of engineering, really) comes on the job(s).

~~~~~~~~~~~~~~~~

PS

I noticed at Amazon one of the For Dummies books is on mechanical engineering. Looks good.

In general I have found it risky to buy technical books that I have not inspected in my own hands. The trouble is that it can be too specialized or too general and it may spend too much time on what I already know or may require more background than I have thus far. If you have access to a bookstore at a university offering engineering degrees, you might find the “just right.”