Thread Definition and 572 Threads

This is related to another current thread https://www.physicsforums.com/showthread.php?t=426307" wherein yuiop presents a very convincing demonstration of non-reciprocal proper time differential between an accelerated system AF and an inertial system IF between two points A and B In...

I know some members like to go hiking different places, and there are various pictures posted in Nature threads. But this is for sharing information on hiking and hikes that folks have done or would like to do. Explorer 6 Days, 6 States, 6 Peaks...

Not the usual "how to get research" thread... I've worked with professors before during the academic year and am doing so currently. I've done an REU also. My question is: how does one ask a professor for a (paid) research opportunity for the summer? Simply asking a professor to work with...

I have a 15-year-old who wants to go into astrophysics, applying either quantum, or atomic/molecular/optics disciplines. My understanding, from reading Zapper's thread, is that she should get a BA degree in physics then specialize at the graduate level in astrophysics. Is that correct...

Hi there. Sorry for the lengthy thread! Please persevere :smile: I have seen that there are many of these threads - so apologies for the bits that overlap. I have tried to keep this as 'original' as possible - but with all of the help I have had so far from browsing this forum I couldn't...

I recently attended this lecture by Physicist Daniel Sheehan, any opinions about the 2nd law soon violated in Laboratory Experiments? (and we are not talking about background fluctuations, etc). Experimental Challenges to the Second Law of Thermodynamics D.P. Sheehan, University of San...

From http://star.tau.ac.il/QUIZ/ website: This problem can also be found on page 32 http://kvant.mirror1.mccme.ru/1990/05/resheniya_zadach_f1206_-_f1212.htm , but it's in Russian so might be hard to read... Can someone explain this solution? Is it always true that F=Fo/2? Don't we need...

"Ben and Jerry's 'Boston Creme Pie" Ice Cream" Appreciation Thread Truly amazing stuff going on in that container. those who know, know. I only hope to one day truly understand the science behind why this is so delicious. until then, i shall enjoy and appreciate it. - may scientific...

Rule 1) Absolutely no religious references, only spiritual and philosophical Rule 2) God may be discussed in this thread Rule 3) God is not a person, physical being, or anything with any type of anthropomorphic traits for the purpose of this discussion (i.e. does not talk and certainly does...

So after posting the blur contest, I did some experimenting with trees in the wind and the sun. Camera on tripod, telelens 70-300, all controls manual, exposure 1/4 sec while zooming in Same exposure but letting the wind do the blurring work Same exposure while making circles...

why is it that you post on 'pf random thoughts' once and get notifications for eternity but have to keep on checking 'best guitarist ever' for new posts?

Anyone listen to this show? It's about the most interesting show on imo. For the people who don't know what coasttocoast is about it's a radio show that talks about lots of "wierd" topics. Anyhow tonights episode... http://www.coasttocoastam.com/ includes an interview with Buzz Aldrin so...

I've seen a few people posting their failures and successes in various threads, so I figured it'd be a good idea to have one combined thread where you post how you did this semester. What classes did you take? How did you do? Did you get any research done? What other trials and tribulations did...

I thought it might be fun to have a thread to show our fossils. Everyone dig up your fossil picks. I found this rock this morning. The fossils range from 400-500 million years old. I'll post more as I dig my pictures out. I'm posting the kansas fossil page for what's on this rock (from...

Another "Late in Life Physics" thread I should really say "Really really late-in-life" I'm 56. About 20 years ago, I flushed myself out of grad school (physics) largely over just being fed-up. Lately I've been reading again because of the huge number of very good books immediately...

Is there any point at all in learning Latin?? I know this is the 21st century, but there must be some little use for it right? For Mathematician/Physicists.

I was shooting some macro pix in the park today. Actually I was targetting this lichen in that pic: and this one: But it's more about the new life: Feel free to share your spring pictures.

Find an interesting article about a new technology, new design, and whatever else is related to things that fly? Post her here!

At 733,000+ views, it looks like The Caption Competition thread in the Fun and Games Forum has a chance. Do we have any other contenders?

So, the time has come that grad school decisions are coming in. Anybody received any acceptances yet? I have applied to 8 schools for a master's in math and have gotten accepted to two - Miami University of Ohio and Bowling Green State University.

I drew a picture of Leonardo Dicaprio. Here's one I drew of Jackie Chan.

Whaaat? Nobody has started a first post thread? Jees. Fine, I'll be the radical bad boy and make it. Hi! I'm Joe. Nice to meet you all. I'm a Physics Major in Western Massachusetts (no e, lol) and currently attempting to find a new college because the one I'm at is just abysmal. I've...

Hi, I was just wondering why paragraphs containing inline LaTeX have extra line breaks or line spaces after the line containing the TeX image? I was also wondering why I don't always see new posts in threads I've subscribed to in "My PF" unless if I click on the link to see all subscribed...

Homework Statement Here's the situation: https://www.physicsforums.com/showthread.php?t=363089. First, does a magnetic flux through a rod considered with no surface area makes sense? To reach the result, we have to assume the flux through it to be -BLR since it's going out from the magnetic...

After participating in a more algebra-oriented REU last summer, I would love to try working in some area of geometry of topology this year. Unfortunately this seems to be a pretty rare field for REU topics. Here are the programs I have found so far that have geometry or topology projects...

Hi, I'm learning Bipolar Junction Transistor and need help to confusion which arise so I will keep posting questions which I don't understand to this thread. Thank you in advance. So my questions start: When using hybrid pi model and t model, we determine the dc operating point first. In one...

Stimulus spending (split from "cap& trade" thread) Don't worry, Obama can spend $10,000,000,000 per year for 10 years with one hand tied to the tele-prompter.

I want to tap a NPT (NPT-3/4) thread hole on a plate. And I found some related standards, these standards told me the detailed dimensions of the thread. My question is how to machine the NPT thread with a tap? How to control the parameter mentioned in the standards? thanks in advance!

I can't decide what I should make for supper. As this is a semi-regular occurrence, I figured I would pawn off the decision on you guys ask you guys for advice. I can't be the only one who has trouble deciding what to make all the time. Just post whatever you're making for supper each day...

Homework Statement Hello, the question itself is pretty abstract. When pulling a thread roll, there is an critical angle, where the thread does not start to unwind itself. Instead, the thread roll itself starts to move. Derive an formula for determining that critical angle. Homework...

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Afternoon everyone, I am slightly confused... Basically, i will be purchasing a force transducer from a company called HBM. Now, on their data sheet it shows that there are two tapped holes either end of the transducer, designated by G and G1. I am using a 125kN transducer, and for G...

I've been browsing the forum, but I haven't found a way to solve this thing, which has been frustrating me for quite a while, I'm trying to develop a simulation of cue formation and propagation on cars on a single lane road, and of course, I have to compute the acceleration of vehicles obeying a...

Probably a stupid question but... I have a device with a bolt that is designated #6-32 UNC. I need to drill a hole in a surface to for this bolt to fit into. How big should this hole be? If the material I am going to be threading the bolt into is plexiglass do I need to thread the hole I...

Yet another "Which Career/Major?" thread. Hi, recently I've realized that I really need to start exploring majors/careers soon. I figure everyone here would be knowledgeable in that. I'm not sure what kind of information is needed, but here's what I think is related. If you're too lazy too...

Hi, here are a list of questions I have doubts about (I do not want to create one for every problem so as not the spam the forum) Q1. Homework Statement My senior gave me this problem. Given that the Earth's radius at the equator is Re, and the radius at the poles is Rp, express the ratio...

https://www.physicsforums.com/showthread.php?t=335357

Where was my MS in CS or MS in IS thread moved? Can it be accessed from the main forums page? If I can't find it, how can anyone else. Thanks, cswave

hello everyone, this is my first post. Right now I am trying to figure out which equations to use to solve the following. I will have a block that will a threaded rod through it. This block will be next to another larger block. In between these blocks are going to be metal samples. Now...

"L di/dt" vs. "i dL/dt" I have heard many times that the positive "inductive" part of a circuit's reactive power is equal to "L i di/dt". I also know that "L di/dt" is just one of two terms that is derived from applying derivative of "L i" with respect to time. The other term is "i dL/dt"...

Yet another "which math course to take?" thread Dear PF members, First, I would like to apologize in advance for asking this type of question repeatedly. I just haven't made my mind yet, and I just think getting another advice from PF members might be helpful. So, I'm going to be a...

If we can shoot a photon outward, at velocity c, why is it that the body that shot it outward is not traveling away from the photon with velocity c?

Please delete << berkeman merged two threads >>

I am trying to do some preliminary calculations for a basic lifting device but some of my numbers seem to be out-of-wack. Could some kind soul take a look if you have a minute spare? Motor Data (max efficiency) RPM: 8311 = 870 radians/sec Torque: 9.213N-cm = 0.09213N-m Output Power = 870...

is this the nazi physics fourm...sure no American..uknow free stuff..like speech..and so..well.2bad..so sad..Cu..no want 2b u..huff...huff.ratz ! be well. still can't spell

It's one of my passions. There were a few earlier threads in which it was discussed, but I decided to start a new thread devoted to mountain climbing and trekking. The 2009 Climbing Season in the N. Hemisphere is in full swing. http://www.k2climb.net/news.php?id=18533...

i've been away more than 5 yrs and can't find the thread that used to tell you how to code latex. you could practise there too without burdening others with your errors. where is that thread? or something similar? in friendship, prad

A while ago I saw a rainbow while I was driving. The end of the rainbow lay right on the hood of my car. When I came to a stop, I popped the hood to see if there was a pot of gold in there. Of course, by then the rainbow was gone and so was the gold. I said I would post about it, but forgot...

I thought it might be fun to have a thread to make your head explode! By means of posting some of your favorite mind-bending paradoxes. I just heard a new one (for me) today that I thought was pretty good, thought I'd share! What if Pinocchio said "My nose will grow"?