Thread Definition and 572 Threads

Ever wonder if and/or how much you should tip for a professional service? Post your questions and preferences here. I shall start off, because I went to a weird restaurant this past Monday and I didn't know what to do. There's a burger joint near me called Smashburger that just got built...

Post your drunk thoughts here (AKA, not thread worthy). Beer induced brain fart 1. When you microwave your dinner with clingfilm sealed over the top, the electrons in that air pocket get excited and the pocket expands (due to the air molecules moving faster right?). You get a clingfilm...

I am picking this up as a continuation and extension of the idea laid out e.g. in @davenn 's thread "The Sun today - 9 July 2017 - nice spot group" https://www.physicsforums.com/threads/the-sun-today-9-july-2017-nice-spot-group.919696/ See also (for continuity purposes)...

Because I just got started on John Varley's Dark Lightning, about an asteroid converted to an interstellar vehicle. Nice word pictures there. Any, some possible help for the person asking the question. Original thread is closed.

When Bell says that the thread in put under "intolerable stress" and breaks, what happens then? Suppose that instead of the thread there is a light rod, which breaks at the point of attachment to the back spacecraft , so it is left sticking out backwards from the front spacecraft .. In the...

I see a lot of posts here in the writing and world-building forum that ask for help in creating a story, but I rarely see any actual stories! Perhaps you've never shown your writing to anyone else or maybe you've never gotten to the part of writing where you actually do some writing (it's quite...

[Mod note: Thread moved from General Discussion forum, so no homework template is shown] So - I've no idea where to write this but... I was looking at this post : https://www.physicsforums.com/threads/car-rolling-down-a-hill.302812/ And started to answer it as it was similar to some stuff...

Homework Statement Hi, I want to know is there any role for left thread in inorder traversal. Homework Equations There is no equation but there is an example image of the tree which is attached. After traversal we would get: Start at leftmost node, print it (1) Follow thread to right, print...

In this thread I gather my questions concerning derivations in the textbook of equations and of solutions to the exercises. I hope every student and professional will benefit from this thread. I'll start in the next post.

Homework Statement (please do not read anything not english) Homework Equations torque=r cross T and I alphaThe Attempt at a Solution I feel that the 3 cases will be different every time but I can't get the hang of the equations.

Hi. I'm at the second year to get my bachelor degree in physics. I actually know the fundamentals of physics. I was looking some threads on PF, then I found this one https://www.physicsforums.com/threads/is-qed-nonrelativistic.900451 My question is, given that I have approximately the knowledge...

Where is the current location of the how-to-use latex sticky thread? Would it make sense to put this thread in the section on latex and math software? Or is it already in that section and I just don't see it?

Since I don't see a thread for this already, I'm making one. This thread is to post updates in your application process, notably acceptances or waitlists. I applied to SULI at Argonne; they first opened applications up for staff/group review Jan. 26th, and I got an offer in the HEP division...

Hello there! I am a newbie on the physics forums. I saw a thread which I wanted to answer because I had a better answer than the one given in that thread but the thread is closed and it is written there that 'you have insufficient privileges to reply here.' How do I get sufficient privileges...

Where can I find the very first thread posted on PF? Is the author still around?

Tonight (as of the time of this post) is the first televised presidential debate between Hillary Clinton and Donald Trump. Moderator: Lester Holt, Anchor, NBC Nightly News Location: Hofstra University, Hempstead, NY The first debate will be divided into six time segments of approximately 15...

that a thread about why the world does not exist does not exist?

Here is a thread of challenges made especially for high school students and first year university students. All the following problems can be solved with algebra, trigonometry, analytic geometry, precalculus and single-variable calculus. That does not mean that the question are all easy. For...

Hello , Please see the attached image , in first case thread A is pulled with gradually increasing force while in second case an impulsive force is applied on thread A ? Which one breaks first in the two cases ? I think in the first case , thread B breaks . In second case , thread A breaks...

Is there a reason (other than tradition) why lamps in the USA use threaded tubing that has an "IP" thread standard ? Does Europe have a better approach ? I find it irritating that the nuts and connectors in the main part of local hardware stores don't fit the threaded tubing in lamps. You...

What is not one of those fields? As long as a significant fraction of the population would agree to a law that bans atoms, ... [split from this thread: https://www.physicsforums.com/threads/stunning-reversal-in-sweden-re-nuclear.875103/ ]

Every time my IDM (internet download manager) starts, I see only 8 threads running. How can I run 32 threads at the same time ? :biggrin: Thanks IDM super users and developers.

Homework Statement Charged metal sphere hanging on an isolated thread of negligible mass is put in a homogeneous horizontal electric field so that the thread makes a 45 degree angle with the el. field. What angle does the thread with the sphere close with the el. field after we remove 40% of...

In post #4 of this thread the latex engine seems to go haywire halfway through a 'display math' section delimited by double dollars. The same code, with the PF-specific breakouts for in-line tex converted to latex standards, works perfectly in my offline latex engine. Further, to my surprise...

SO fun story, I'm working on a client server dealio! The flow of operations should be: Server listens on port 9999 Client connects to port 9999 Server tells Client to connect to new port # (to allow for more connections) Server launches a thread and listens on new port # Client disconnects...

If I were to be studying for an exam and came across things I didn't understand, does that also qualify as coursework? If so, what topics should be posted in the "main" forums?

Homework Statement http://gpschools.schoolwires.net/cms/lib05/MI01000971/Centricity/Domain/272/Chapter%205%20MC%2013.pdf It is problem 22 on page 7 of the document: A block of mass M1 on a horizontal table is connected to a hanging block of mass M2 by a string that passes over a pulley, as...

Homework Statement A spool of thread consists of a cylinder of radius R1 = 6.6 cm with end caps of radius R2 = 9.3 cm as depicted in the end view shown in the figure below. The mass of the spool, including the thread, is m = 290 g. The spool is placed on a rough, horizontal surface so that it...

Homework Statement A heluim filled spherical balloon with a radius of 40 cm got tied into a uniform thread (uniform density) the threads length is 2 meters and its mass is 50 g the balloon ascends when left and ascends a the thread for h meters before it stabalizes again given the empty...

Hello everybody! I want to know where my fellow PF'ers stand on the upcoming US election. I found this neat website which calculates the candidate that would theoretically be your best choice: http://www.isidewith.com So please fill out the quiz and indicate your outcome on the poll, not the...

Homework Statement If an object is hanging by a thread, how fast must it be twirled around in order to break the thread? (must also provide explanation of why this is the velocity). As a part of a lab, pick a certain mass. Attach to light string (easily breaks) and pull the string through a...

Dear PF Forum, If someone quotes your post from thread other than your quoted post. Do you get an alert? For example like this

However the question here is phrased a bit differently: Is the relocation of a piece of information from one spot to another in a shorter time than c-speed light would cover the distance theoretically possible? Or at definitively least not ruled out to be impossible. From what I know of...

Hi guys! Like the title says, I'm applying for 10 astrophysics-related REUs, and I'm a frosh, so I have few other people to ask for guidance. Please let me know if this is a good baseline to add to. Thank you all in advance!Sitting in the middle of an abandoned lab, late on a Friday night, head...

WARNING! This thread contains spoilers for Star Wars: The Force Awakens. If you have not yet seen the movie, we strongly encourage you to turn around and return once you have. It seems like a good idea to branch off a new thread from the old one to prevent spoilers (on that subject what is...

Yes I fully understand that the people on this form have all of the schooling , degrees and knowledge that they have accumulated to accomplish all kinds of things. And buy my simple question, I did put on display my complete lack of knowledge in the things pertaining to my question. And you are...

I am reading P.M. Cohn's book: Introduction to Ring Theory (Springer Undergraduate Mathematics Series) ... ... I am currently focused on Section 2.2: Chain Conditions ... which deals with Artinian and Noetherian rings and modules ... ... I need help to get started on Exercise 3, Section 2.2...

Hello! I would like to ask for your help with understanding a few things connected to the following problem: 1. Homework Statement There is an (infinitly) long thread, on which small beads can move without friction. The beads with mass m are lined up on the thread with a constant distance d...

Hi! I'm in a situation with threads that are being torqued, and unthreaded, and then torqued again hundreds of times per day. While torqued they are required to lift thousands of pounds of load. We've experienced failures where the threads appear to have worn/galled to the point that they...

How do I find the force acting on the helix of a thread. Say if I'm using a torque wrench to tighten a nut and compress a gasket between nut and a mating piece and give 100 ft.lbs of torque how much of it will be available on the helix of the thread (say a helix angle of 0.67 degrees)...

Homework Statement I have the proposal of making a math test thread in which instructors test student's knowledge in a specific topic. If you agree then post the same thread. For example: you have the topics that will be covered in your next exam such as permutations, combinations, bayes...

Hey guys, I need an explanation on the definition of the electric field. It was said in a post that " the definition of the electric field is defined in terms of how it is measured or tested". What do they mean by measured/tested?

First of all, I'm sorry if this is not the right place to put this, but I thought it would be relevant to a science/math resources forum (so feel free to move this or do whatever). One idea I was considering is if there could be a thread that contained an index of important things that one...

Dear experts, when a a stone at the end of the string is rotated with a high speed so that the string is suspended making zero degrees with the plane of the ground, how do we analyze the system from the rotating frame.

Hi, Apologies; In spite of the numerous excellent threads that exist discussing GR books, I felt compelled to create another one. I'm taking a first course in GR & Cosmology, and am trying to select a textbook as the main 'roadmap' through GR. This is a first course on GR in the UK, which is...

I adjust my tap to produce a thread of water about 2 mm in diameter. It breaks up into droplets about 10 cm below the spout. I touch the thread near the spout with the tip of a single hair (from my head). I see ripples (standing, not travelling) on the thread 1-2 cm below the hair. The strange...

Dear staff, I just read an interesting thread: https://www.physicsforums.com/threads/can-you-check-my-equation.827896/ The thread was created yesterday 16 August 2015. But now, 17 August 2015 is already closed. I see no offending content, no protest of the mentors, but it's closed anyway. Can...

OK so i finished my first course of Differential equations at Uni and i have some curious questions The last equations we solved were PDEs solved with Variation of parameters and having to homogenize the boundary conditions They were all Sturm-Liouville problems as they called them, we assumed...

Homework Statement A coil of 25 turns of wire is suspended by a thread. When a current flows through the coil, the tension in the thread is reduced by 4.0 ´10-2N. http://members.shaw.ca/barry-barclay/Self-Tests/test11/Magnet20.gif Homework Equations F=IBL B=nμI[/B]The Attempt at a Solution...

Hey everyone! So, I am in a dilemma. I have a mathematics bachelors degree with a minor in physics, but many more course than just a minor, really it is like 2-3 courses away from being a second major. Anyways, after I received my math degree and physics minor I got cold feet about going to...