Thread Definition and 503 Threads

Cant someone start a tutorial thread? Cant someone start like a tutorial thread? :confused: Looking at the potential here :bugeye: , if we could start a tutorial on a topic, maybe under a separate subdivision, and post there (not problems but different concepts that each one could bring out)...

Here, I have a question. 2 persons are holding a rope of negligible weight tightly at its ends so that it is horizontal. A 30 kg weight is attached to the rope at the mid-point which now no longer remains horizontal. What is the minimum tension required to completely straighten the rope...

So, I have a question about latex, but the thread in the tutorial section is locked. Is there another place I should post it? Anyway, the question is, is there a nice way to do commutative diagrams with latex? I'm talking about those pictures with sets and arrows between them representing...

Everyone has those little niggles that really p you off, spelling nazzis, people who listen to I-pods on trains at a volume whereby everyone can hear the music, the lyrics and anything else, I don't like hardcore dance at the best of times, but at 7 in the morning, I really could do without out...

Since there are only 20 minutes until 2007 in my time zone, I'll report back from 2007 to everyone who isn't sharing the same time zone and say what's it like in 2007. Any questions about the changes in the world shall be answered. :biggrin:

I just hought about it, and why is there not a correct definition of light? Some says they are particles, others say they are waves. Some say they are energy "packages"... If they are waves, they need something to travel through, as i understood as the elecromagnetic field that is...

time to kick off a game of smurfball here...post your randoms as per the uge! :smile:

i need to compute lim (a^n-b^n)^(1/n) when a>b>0. lim ((3n)!/((2^3n)n!(2n!)))^(1/n) where i need to use the lemma that: if an>0 for every n, and lim(x_n+1/x_n)=L then lim x_n^(1/n)=L, how to use it here? for the first i used practically everything i know, the formual for a^n-b^n, and the...

Im trying to figure out this problem, but I am not sure if I have the equation(s) I need. "A ball is thrown horizontally out the window of a building with a velocity of 8.0 m/s from a height of 2500 m. How far from the base of the building will the ball land?" a) 54 m b) 60 m c) 90 m...

Another one of those annoying best "text" threads...If you would kindly have the patience to tell me about your experiences, that would just be dandy. Best Quantum Text: Shankar or Sakurai? Best Linear Algebra Text: Axler or Friedberg? Best Real Analysis Text: Rudin or Royden? Best...

Ok sorry about that, here is the actual problem: g(x)=sq.rt.(2-x) Find the inverse of g(x) ok the answer is -x^2+2, but how come the domain is [0,infinity)??

Inspired by Zz's regifting thread, I would like to ask: What would be the typical mathoms of our time? :smile:

That's right folks, college football season has finally arrived. So declare your allegiance, talk some trash, and gang up on any USC or Ohio State fans. Are there any Notre Dame fans out there? It's ok if you're afraid to come forward because you know your team is overrated and is going to...

I'm sorry I've looked everywhere. Normal search & google search. I guess I should have bookmarked it. Anyone know what I'm talking about?

Since many of us have personal interest in tropical weather, including myself, I thought it might be helpful to have a thread to keep up with it before it happens. Especially since this season is forecasted to be "very active" (NOAA) in the N. Atlantic. :frown: I think my main objective with...

There was a thread where the thread starter pointed out a video lecture where a MIT prof claimed that KVL was incorrectly used in the analysis of self inductive circuits in almost all textbooks. I thought it was an interesting read and wanted more opinions on the idea, however I cannot find the...

So that we do not disturb the Freidel et al thread, I will start another based on Careful's remarks: First comment: if you had made any effort whatsoever to look at category theory over the last few months you would realize that the assumption that it "isn't deep enough" might be a little...

Where the hell did my thread go? https://www.physicsforums.com/showthread.php?p=1025395#post1025395 Here it is again: About the theory put forth by Planck (Planck's constant) that everything is determined and measurable...even human nature (if we had enough data...like asimov touched on...

Kea had a good idea in the MIP forecast poll thread. https://www.physicsforums.com/showthread.php?t=124951 Out of innate gallantry o:) and a desire to make myself useful, I should like to start this thread, which I hope other people will be able to make something out of. The paper in...

This isn't directly a request for homework help, since classes won't be starting for another two months, but I suppose it will be helpful to homework because I'll be taking Applied Analysis, Mechanics, and Electromagnetism, all of which include vector calculus. Given time, I will try to work...

Calling all food lovers and connoisseurs of PF . A thread to post anything and everything about food. Share your favourite recipes, your kind of cuisine and favourite dishes, dining experiences, or even your kitchen antics and fiascos. Let the food fest begin and remember, gluttony is not a...

The Crother's thread obviously needs a new home, as the OP of this thread doesn't want it hijacked to discuss Crother's issues. I'm not sure how much longer the discussion is gonig to go on, but as a courtesy to the OP, I'll just move further discussion here, to avoid hijacking his thread...

The "I loathe football" thread. This will be a gathering place for all of us who hate football. Post your snide comments, sarcasms or just express your anguish that otherwise intelligent and well-balanced individuals are now totally f***ed up. :smile: :smile:

The "Quark" thread The "Quark" thread seemed to have been indiscriminately locked (I appreciate a last post to say why). I still have question about quarks. From what marlon and arivero said, it sounds like quarks have not been "seen." Is this so? Why does the color force and strong force...

Congratulations yomamma! https://www.physicsforums.com/showthread.php?t=63689&page=704

Hiya, We have a Disney appreciation thread here. Why not have a DISCWORLD thread! Come on, you fellow Discworld lovers! Post your experience, favourites quotes, trivia or thoughts on Terry Pratchett's series here. I've read every one of them exept Thud so far. I'll start of with some...

Photograph from the Associated Press: http://news.yahoo.com/photo/060504/480/dn10305042248;_ylt=AsJpCA358j22VlfatZq6DPFH2ocA;_ylu=X3oDMTA3bGk2OHYzBHNlYwN0bXA-" (and the corresponding http://news.yahoo.com/s/ap/20060504/ap_on_re_us/pesky_parakeets" ) The discussion topic will invent itself...

I am Wes, and I have a Physics exam this morning at Laurentian University. I am actually a Biology/Education major and will likely take a Physics minor. This exam is on basic physics and some more advanced calculations. For this exam, we are allowed to use all course notes and laptops for...

QG status paper---explication only thread If you wish to critique or challenge the Rovelli paper about current QG status, please start your own separate thread to do that. It is a short paper with a lot in it and it need first of all to be EXPLICATED which means paraphrased and unpacked--the...

Another thread regarding "voice" How many of you find the apparent perception of your voice while you're speaking and the actual voice to be dissonant? That is, you have the intentions and the perception of speaking in a cogenial and moderately pitched tone (as the words are leaving), while...

http://www.fortunecity.com/emachines/e11/86/qphil.html I was wondering if anyone knows of any other interpretations of the classic two slit experiment other than the Copenhagen interpritation, I've heard there there is a Bohmian interpretation(anyone know anything about how the wierdness is...

Who wins? Who loses? Post your guesses! :smile: Here's a list of the nominees: http://www.oscar.com/nominees/list.html

I remembered seeing a thread with links on how to study science here on PF. I checked in academy and career and looked through 500 topics on search but i couldn't find it (prolly because I'm too tired). I'm not asking anyone to find it for me, but if anyone of you guys remember where that thread...

I know you've all been wondering who's killing threads since New Years. in tenth place we have a two way tie with 5 kills each: Lisa! and Franz a three way tie for 7th place with 6 kills each: Zooby, Math is Hard and Matthyaouw 6th place 8 kills:Mattmns 5th place 11 kills: Evo 4th place 12...

The intent of this thread (for now) is to introduce the basic theoretic principles of rotational/vibrational spectroscopy, follow this up with a brief sketch of the expermiental techniques and finally zoom in on the experimental and theoretical aspects of a specific technique of recent interest...

A laser in visible is used in Raman spectroscopy and the resultant spectrum is in IR and Microwave region(which means molecular vibrations and rotations are excited), what type of interaction is this that induces these levels? ( I cannot think more than..."To be Raman active molecules should...

:cool: Hey ya'll, I was wondering, if there anyone has discussed topics dealing with nanotechnology. For instance, what are the latests developments, how far has the cutting edge advanced, aside from sensors is there reasearchlooking into programable nanobots, what sorts of materials...

yo mam so fat that they needed to put speed bumps at the buffet line to slow her ass down! post your "yo mam" jokes

About cryptic crosswords http://en.wikipedia.org/wiki/Cryptic_crosswords" Here is today's crossword http://www.hindu.com/2006/01/16/stories/2006011600060900.htm" I have put my guesses to the right of the clue in white (after the "--"). If you don't want to read my guess and want to...

A general unification of magnetism&gravity and Strong and weak forces? http://www.heim-theory.com/ Saw an article in New scientist about this theory and how it's being experimented on as we speak? Is there anything to it, or is it a flight of fancy? I'm sure someone has some knowledge of...

Hey, what are you doing here? Gee, thanks. Anywho, I didn't do anything for New Year's Eve and the Bucs won the NFC South (Woo!), so I've been celebrating today... since noon. I'm lonesome now, so does anyone want to talk about something? I'll start. Did you know that according to Otto...

You can read lots of these - http://skyandtelescope.com/news/article_1649_1.asp", for example - I thought it might be fun to take a different view! :smile: What were the most notable non-discoveries for 2005? What were the most outstanding failures? I'll go first. In the second...

I know, I'm not exactly making a good impression by making another similar thread to those made one and two years ago, but I had some other questions. Just some background information, the assignment is that I have to construct a mousetrap car for distance (I don't believe speed even came...

The thread was locked down before I could post in it. Amongst QT's temper tantrums a sideline was talking about Aaron Copland... I have to side with Jelfish and say that you guys that are "lernt" in classical music are not so "lernt" if you think Aaron Copland stinks. Take it back right now...

I think I'm going to make coffee. It seems like a good idea. Since I'm a delightfully lazy guy, it'll be instant coffee. I don't like doing stuff. Especially if it takes effort. Yeah.

I was conversing with a penguin friend who's name shall not be disclosed, let's call him, pengwuineo. anyway, i realized, penguins in addition to smelling bad, are crazy. I decided to make-like-a-penguin, and to walk around outside wearing only flip flops. i got back like, over 10 minutes ago...

The "What does Smurf think?" thread. This thread is all about what Smurf, my favorite anti-statist on this board, thinks. Specifically, about what would happen were "the state" abolished. First off, is your version of anti-statism pretty self explanatory? Is anti-statism the same thing as...

I took a history test today that was actually good! It didn't involve memorizing dates and names (well, not very much), it involved understanding concepts and the relation of events to other events. So, instead of failing a high-memorization test due to little studying (I have a "good"...

One second, I'll create the poll then add the link. There weren't enough options to list them all so I took out the ones I thought would be least common. If a mod can expand it, please do so. Here's one test here: http://www.humanmetrics.com/cgi-win/JTypes2.asp If you know any others...

Side Topic for "Great Depression" Thread The demand for oil is also on the rise though. As vast as these reserves may be, all that does is buy us a little more time to figure out alternatives/fight over it. It will still run out eventually.