Forum Definition and 414 Threads

Well although the thread topic speaks for itself I want to introduce myself here. I created an account in this forum a while ago and I've been checking it a bit So yes! I want to participate but I know no one, I tried to find the topical section in which newbies introduce themselves but I...

Mellow, all Physics Forum member, Please help me to have the answer of question, Why electron spin is +-1/2. What is the reason of integral spin of subatomic particle?

If I want to start using LaTex on the physics forum, is the best way to do it just to learn all the coding? This seems like quite a task for me (I've never learned any computer language thing). I downloaded MiKtex (LaTex software) and was hoping that it would somehow write up the proper syntax...

Hi there, I'm a first year PhD student and was going to ask the forum for some advice on some maths (specifically Fourier) that will be used in my work. However, I wanted to know what the forum/general policy is on what happens should this work ever be published. Would a forum contributor be...

Homework Statement In the electrochemists technique of cyclic voltammetry, the peak current, I, is a simple function of the scan rate, v, according to the Randles-Sevcik equation: Homework Equations I = 0.4463nFAc(nF / RT)^1/2 D^1/2 V^1/2 Where n is the number of electrons transferred, F is...

Any chance I am getting close to the record? jk :) I have seen many in the tens of thousands, has anyone cracked 6 figures yet?

Hello MHB, I am just curious about how many in this forum got apple product :) I got one apple product which is Iphone 4s. Is there also anyone against apple?Regards, |\pi\rangle

Here is the question: Here is a link to the question: Prove this limit. I have posted a link there to this topic so the OP can find my response.

In order to help with server load, we are splitting up the larger threads. This is a continuation of the original Where's That Landmark? thread located here https://www.physicsforums.com/showthread.php?t=270543&page=480

I haven't taken a course in years, so I don't know how modern teachers and tutors use the internet. It occurs to me that one interesting exercise would be to have a student ask a question on various forums, collect the posted answers and then have the student or the class critique them. Anyone...

I am new at the forums and still getting used to writing in Latex. I found that it is easier for me to write my LateX in this editor: http://www.codecogs.com/latex/eqneditor.php and then copy to the physics forum. So, I wanted to ask you guys, do you know any other tricks you want to...

I need to purchase a dress suit for some upcoming research presentations but the Men's Wearhouse in my area has terrible reviews and I don't know anywhere else that sells suits. Anyone know where in the NYC area to buy a suit or any other forums to ask about this?

This forum is ONLY for the discussion of existing science fiction and fantasy stories in movies, books, tv, comics. It is NOT for discussing personal ideas, those would go in the Science fiction WRITING forum if they adhere to the rules for that forum. This forum is not for new ideas or...

Hi n PF, Is there any IRC for Physics forum or similar thing... So that I can ask my doubts real time... Also for windows7 which is the best IRC software. -Devanand T

Homework Statement A tank consists of two chambers, one open to the atmosphere and another closed and filled with a gas. The two chambers are connected by a sluice opening. What is the pressure in the gas, in gauge and absolute terms if the barometric pressure = 742 mm Hg. Difference in height...

Similar to this one, but for Economics where you can get help with Homework, assignments, theories you don't understand, diagrams etc... Thanks!

I am looking for a forum that is similar to PF, except tailored for law students rather than for students of science and engineering. Does anyone have any recommendations? I searched google. Most results give forums for either people who have questions about an actual case (i.e. they are...

I was talking to my physics teacher today about electric motors and used some information I learned here. I'm not calling you guys wrong by any means, I just would like to know what is real. He claimed two things: 1. As load on an electric motor goes up, current goes down (I know this is wrong...

The Philosophy forum will be closing in one week, Monday the 15th. All threads will be closed and merged into General Discussion. The reason is that the Philosophy forum over the past couple years has been almost impossible to moderate fairly and two out of three threads end up locked. Please...

I’m a layman new to the Cosmology Forum and just finished reading through the very helpful, “Effort to get us all on the same page (balloon analogy anyone?)” by Marcus et. al. followed by “Look 88 billion years…”. [If you’re in a hurry see the nice summary by Mark M at cosmo.pdf.] Along the...

I'm having a really difficult time understanding limits from the graph. I don't completely understand how to find if the limit exists or not. I tried to do these for my homework but I don't know if they are right. Could someone please help me understand limits?

I've made a few efforts to learn to program in the past, but I've never lasted more than a few days. What are ideas on ways to make it fun? Websites maybe? Or forums? For learning science/engineering principles, this forum is great. Do you guys have suggestions for ways to make...

Hi, I have been looking around for popular, well-used, and informative forums for alternative energy. I can't seem to find any great ones using google/bing/duckduckgo. If anyone has any suggestions it would be great! thanks!

Hi, why is the debunking forum gone? does it have to do with the fact that after the discovery of the Higgs. Science is complete and the universe is purely nuts and bolts and humans mere flesh and blood indistinguishable from animals and there is no mystery left in the world?

Well, the title really sums it up to be honest. Are we allowed to write our own stories and post it piece-by-piece as we write, here on this forum? If so I would love to do something like that. I may even include some of the members as characters even ;)

In this forum, it is possible for writers to ask for help with science-fiction or fantasy stories. Since science-fiction is speculative in nature, some degree of speculation is allowed here. However: There can be no speculation about the real world and about known science. Rather, all...

Do LaTex tables work in forum posts? I've never used them before. Today I tried copying several examples from pages on the web such as: \begin{tabular}{ l c r } 1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9 \\ \end{tabular} which on my browser doesn't show up as a table. I tried...

This is my first post on any message board so bare with me on any grammatical errors I make in the post. I will be heading into my senior year of high school and I plan on majoring in physics. But I live in a rather rural community and high school courses aren't considered challenging. We have...

i am new to this forum so if i do any mistakes then kindly guide me. i didnt know where to post this question of mine. i was wanted to go deep in physics, but in India not much importance is given to this field as a career and i was never motivated nor did i receive any help from any of my...

Hello, I am new to the forum but figured I could ask some intelligent people about an idea that has been bugging me. Here goes... I am trying to make a generator that is run by an electric motor but the electric motor runs off the generator head at the same time. The way I...

I never click ads, I use adblock plus, and I assume that most other people also rarely click ads. I know that ads can still be valuable by increasing my awareness of a brand/idea though. My question is: Do ads still pay well? I've read that online advertising is becoming less viable as...

Original Title: could you help me on this trigonometry function Hi rlaydab, :) \[\sin^{2}n\theta - \sin^{2}(n-1)\theta = \sin^{2}\theta\] \[\Rightarrow [\sin n\theta - \sin (n-1)\theta][\sin n\theta + \sin (n-1)\theta] = \sin^{2}\theta\] Using sum to product identities we get...

Original Title: Please Need an help on this integral! Hi chamilka, :) \[\int_{0}^{1}x^{a+b-1}(1-x)^{c-a}(1-x^b)^{d-1}\,dx\] Using the Binomial series of \((1-x^b)^{d-1}\) we get, \begin{eqnarray}...

Hello... I'm trying to figure out how many magnets I need to put on one side of a piece of sheet metal in order to sufficiently magnetize all the surface area of the other side to a specific attractive force to other pieces of steel in contact with the sheet. It has been too long since...

I'm Sammy I've been lurking through the physics forums for a while and finally decided to start posting. I enjoy the good advice and humor I've seen throughout the forums. I'm glad to see that there's a forum community just for our kind of crazy. :P

Title: how do i show something is a solution without solving it? 2nd order DE Hi ouchimdead, :) The only thing that you have to do here is to find the second derivatives of \(y(x,t)\) with respect to \(x\) and \(t\). Then it could be easily seen that they satisfy the given differential...

Title: Website/Article of use for solving this? Hi trig108, :) I think a good place to start with is Paul's Online Notes: Differential Equations. It gives a very simple introduction which is easy to understand. Also "A First Course in Differential Equations by Dennis Zill" is a nice book...

Title: How do you do this problem? Hi mortifiedpenguin1, :) I presume what you meant by a "closed triangle" is in fact to show that the given three points are non-collinear; so that a triangle is uniquely determined. You can show that the points are not collinear by showing that the two...

Title: Find a standard basis vector Hi saqifriends, :) We can use the determinants to see which standard basis vectors are linearly independent with the given two vectors. \[\begin{vmatrix} 1 & 0 & 0\\-1 & 2 & 3\\1 & -2 & -2 \end{vmatrix}\neq 0\] \[\begin{vmatrix} 0 & 1 & 0\\-1 & 2 & 3\\1...

Hello,everyone. I want to know other Nuclear Engineering forum or newsgroup.Thanks!

Title: Prove this limit Hi sluggerbroth, :) \begin{eqnarray} \lim_{x\rightarrow 1}(x^2-2x+4)&=&\lim_{x\rightarrow 1}x^2-2\lim_{x\rightarrow 1}x+\lim_{x\rightarrow 1}4\\ &=&1^2-2+4\\ &=&3 \end{eqnarray} Kind Regards, Sudharaka.

Hello all, I am a mechanical engineering major who is fascinated with control theory. At my school you can specialize in controls as either a mechanical major, or an electrical major. Does anyone know if being a mechanical major is a disadvantage at becoming a control system engineer? My...

Hey, I'm Cameron and I live in Florida. I graduated from HS in 2008. After a few years of "exploring" my options, I'll be attending college this fall semester. My ultimate goal would be to get involved in anything to do with commercial space programs. Right now I'm pondering which major and...

How do I write X bar with the bar over it to denote a vector? I discovered that if I compose a Latex equation here that I can copy it into a Word file. Is this true of all the symbols? Same for sub and super scripts. Is there a software tool that I can use to write Latex outside the realm...

One of the great benefits for me during discussions and debates here on Physics Forums, Politics & World Affairs (P&WA) is that I gain personally from participating. Questions on controversial issues get posted and then the ideas, beliefs, and opinions of our members begin to accumulate for...

At least as far back as the Greeks people have been trying to understand things by looking at lower and lower levels to find the first principles which determine all things. We break things into their components, and then into materials and then into compounds and then into atoms. This works...

What's REALLY wrong with this Forum... Logged on this morning, and noticed that Evo, had once again, mercilessly, locked an apparently well meaning thread. Was it posted in the wrong section?(Looked like a philosophy topic to me) Were there no "reliable" sources for the information? What...

I want to know how can I have the latex system on a vBulletin forum. I searched for it but there was so little about it. Thanks

Maths is a precice science*, but when using maths in the real world most people, including many mathematicians, generally take 'short cuts' which result in specifications of a problem or descriptions of a solution which are strictly incomplete. This has a number of advantages: it is quicker...

1. There should be a separate (sub)forum for NT. ... and one for abstract algebra, for that matter! 2. Show that there are infinitely many n such that both 6n + 1 and 6n - 1 are composite. Without CRT, if possible. My work... let n = 6^{2k}. Then 6n \pm 1 = 6^{2k + 1} \pm 1... Hmm. Having a...