Pure Definition and 482 Threads

Is water a pure substance? I had a question on a quiz and it said which is not correct. I answered "Water is a pure substance" and got it wrong. The correct answer was "Elements occur only in the form of atoms." Explanations please, thank you.

When charged particles aren't moving they produce an electric field. As the start to move and accelerate, the electric field intensity gets lower, but a magnetic field is being made and it increases in intensity. If the particles reach the speed of light will they produce pure magnetic field...

Are there any reason compelling you to go into pure mathematics beside passion? Aren't you afraid that your discipline will not yield any practical benefits for mankind?

I'm currently doing a MS in physics. The way I'm progressing, it looks to me that I'd probably have to take 3 years to finish the thesis. This is because I'm having to take extra classes since I didn't have a critical 1 year class (E and M) during undergrad; I didn't major in physics. I'll be...

Hi guys, I am reading some paper on Mellin Transform and its application in signal processing and I am totally stumped by phrases such as lebesgue space, square integrable, isometry, automorphism, measurable and essential supreme and such. Of course, when I look them up one by one I sort of...

Homework Statement Let q be a mixed state which we mix from pure states. What are the weights we must take for the pure states, respectively? Let us start the solution with the two-state system. The Attempt at a Solution My problem is I can't decypher what the problem actually is, from...

I have a sample on which I think carbon is formed physically but not chemically. What is an analysis technique to determine that there is carbon for sure?

Hi everyone. I have been presented with a problem- to produce a set amount of pure, dry oxygen in any way I can, provided it is safe and accessible. I have chosen to tackle the problem by heating silver oxide until the silver and oxygen separate, however there remains the problem of isolating...

Is the Higgs boson only a particle of pure mass? It has no charge, no spin, no color, no flavor, etc. Does it have any other non-zero characteristic besides just mass?

Applied mathematics vs. "pure" mathematics in high school? I've just started working through "Basic Mathematics" by Serge Lang. It immediately struck me, when I skimmed through the pages, that there is a large emphasize on proving things and manipulating expressions, and very little exercises...

Hello, I've been pursuing a second bachelor's degree part-time for a while now at a Group III school. I just found out, somewhat unexpectedly, that I might be able to transfer to Georgia Tech (a Group I school) with relative ease to complete my degree as a full-time student. GT is...

Getting into a Phd-good or bad?? Hi,this might sound familiar.I quit my masters in automotive engineering from a very reputed university in Germany.I had finished all my course-work in 2 years,had 1 year of thesis and internship left.But,I couldn't take the emperical dominated engineering...

(a) (i) Express \(\sqrt{48}\) in the form \(k\sqrt{3}\), where \(k\) is an integer. (1 mark) ...(ii) Simplify \(\displaystyle \frac{\sqrt{48}+2\sqrt{27}}{\sqrt{12}}\) giving your answer as an integer. (3 marks) (b) Express \(\displaystyle \frac{1-5\sqrt{5}}{3+\sqrt{5}}\) in the form...

[FONT=Times New Roman]1. The line \(AB\) has equation \(7x+3y=13\). [FONT=Times New Roman] [FONT=Times New Roman](a) Find the gradient of \(AB\). (2 marks) [FONT=Times New Roman] [FONT=Times New Roman](b) The point \(C\) has coordinates \((-1,3)\). [FONT=Times New Roman] (i) Find an...

"Pure Recursive Function" for f(n) = 6n + 6n Howdy! First of all I was going to explain a 'Pure Recursive Function' as how my professor defined it: A pure recursive function is stated by only using previous values of the function.. Like: F(n) = f(n-1) + f(n-2) Which means you can't have a...

In the First Three Minutes, S Weinberg wrote: I thought mass gives rise to pure energy in the form of photons. I didn't know pure energy could give rise to photons, I thought photons were pure energy.

Hi there, I am reading several books on quantum mechanics and they mention some concepts on coherently and incoherently superpose a bunch of wave functions. As my understanding, if there are series of wave functions, which satisfying a certain distribution, the coherent way to calculate the...

I currently have a B.S. in mathematics and just got accepted into a Ph. D. program for math. In this program there are 4 different specializations: applied math, statistics, pure math, and computational math. Out of these pure math interests me the most, however, I'm afraid I won't be able to...

I'm an undergrad in college and I've been studying pure math for some time now. I do not really like the job outlook that this path is taking me. My school offers a Masters program in Math Finance (Stochastic Calc and all that). It seems that this more applied field has a greater job outlook...

Homework Statement Hi I am having tough time figuring out how to determine normal stresses σx, σy, σz using the flexure formula. All that confuses me is which moment to take for which σ. My for σx or Mz for σx and so on.. I will post an example question. In the question below, find the...

Hi, If two atoms of the same element form a bond together, would the bond be purely covalent or would it have a small ionic character as well ? If it does have an ionic character please explain why. Thanks

errrr, THEOREM >.< ... oops ... Homework Statement Prove that when edges of a complete heptagon are colored with two different colors, there will be at least three pure triangles.Homework Equations The Attempt at a Solution i can do two pure triangles, but not three :cry: pick a vertex v. It...

Homework Statement I can't answer to that question, and I don't know how to. I have to calculate the average separation between H2O molecules in pure water. Homework Equations The diameter of the molecule is 0.29 nm I think we can use the bohr equation to resolve it? r = (ε0*h2)...

The title says it all. Engineering physicists have more job options than a regular physicist I hear so I'm kind of leaning towards that. Is it possible to get a Ph.D. in physics after a degree in EP? I only ask because physics is my passion but I also like engineering. Also is EP more...

I'm just starting out right now as a math and chemistry major. Should I choose applied or pure math as my concentration? I've been told that applied math will help me with chem, and I agree. However, I also feel comfortable with the theoretical side of things, and it's a large part of what draws...

I'm trying to understand the qualitative relationship of voltage and the a.c. through a pure inductor. My books says that to maintain the current in the inductor, the voltage across the inductor provided by the a.c. supply must be equal to the back emf but in the opposite direction. I'm quite...

Hello guys. Some of you might remember my posts regarding the talent required to become a pure mathematician. I have done much introspection as of late, and I keep coming to the conclusion that I am not enjoying "Pure" mathematics as much as I thought I would. I originally became interested in...

Hi all, I have a little out of track question and I was forced to consider this after reading FQXI Essay competition title Is Reality Digital or Analogue and Kant's Critique of Pure reason simultaneously. If I am not wrong, according to Kant, there are limits of pure reason. Is not the...

I'm finishing up my second year in EE, but realizing that it may not be the right field for me. When I applied to colleges, I didn't really put much thought into what I wanted to study; my parents suggested engineering and I stuck with it. I've always been very strongly mathematically...

I am doing my thesis in quantum information and I am learning the background of it, I met this two things mixed and pure states. I have read a few books and a few articles too. But I still can not get the idea. So If anyone can give some help explaining this, would be such a good help. Either if...

I feel I will explode and must rant about it somewhere Tell me how I have an IB diploma with an extra certificate in physics, five 5's on AP exams, a 4.06 hs gpa, a 4.0 college gpa with all honors courses, am involved in science and honors clubs and whatnot and research, and yet got ZERO...

Should i choose pure mathematics or statistics as a major for my degree? I intend to do my masters n PhD to become a lecturer. which is d better path if i want to be an academician? i also heard dat pure maths esp math proof is vry rigorous but I'm nt sure if i'll like stats.. any advice?

This probably (60%?) seems like a strange question but I have the option of taking probability from either the EE or pure math department and want to know how each will deal with the subject. Here's the course descriptions: EE - Introduction to Probability Theory. Covers the fundamentals of...

I lack talent in pure mathematics. (Although applying mathematical methods has been natural for me.) I am a physics freshman. I can prove and I can self study mathematics given enough time. I guess it's still too early to decide, but, I suppose, I'll be doing theoretical/mathematical physics...

I am wondering what the rest energy (mc^2) is of 1 cubic meter of pure matter (no empty space). Thanks, Jake

The usual description of Schrödinger's cat is that after being placed in the box, Schrödinger's cat in a superposition state of being alive and dead. Sometimes, I see this written as: \mid \Psi \rangle=\frac{1}{\sqrt{2}}(\mid alive \rangle+\mid dead \rangle) This is representing a particular...

I'm sure everyone gets tired of this question, but it's important, so I'll ask anyway. Can anyone make suggestions for good grad schools for pure mathematics? Especially number theory or algebra. I already have a list of about ten of the top tier schools, but it would be especially helpful to...

Homework Statement Derive the pure SU(2) YM theory on \mathbb{R}^4 from the action. Let A_{\mu} (x) be a solution to these equations. Show: \tilde{A}_{\mu} (cx) is also a solution (with the same action).Background The Euclidean YM action \mathbb{S} = - \int_{\mathbb{R^4}} Tr (F \wedge...

Right now I'm a sophomore at a state uni with hopes of getting into graduate school in pure mathematics. When I was a freshman, I surveyed the three major areas of math - analysis, algebra, and topology - and I decided that analysis was for me. Although I did very well in Algebra, I found it...

Hi everyone. Homework Statement We are given N spins 1/2. A rotation is defined as \rho_\theta=e^{-i\theta J_n}\rho_\theta e^{i\theta J_n} on an Hilbert Space H, with J_n=n_xJ_x+n_yJ_y+n_zJ_z\:,\quad n_x^2+n_y^2+n_z^2=1, and \theta isn't related to any observable. Given a quantum state...

I noticed that the temperature coefficient of resistivity of pure silicon is a rather high negative number, so just out of curiosity I wanted to see at what temp the resistivity would drop to zero. The formula is ρ-ρ0 = ρ0α(T-T0) where ρ is the final resistivity, ρ0 is the reference...

Hi. I'm new around here, and from Norway so please excuse my english/any other mistake I make. I have read several articles concerning fusion/fission, and they all say that the "lost mass" is turned into "pure energy". What is meant by pure energy? Is it the new nuclear particles increased...

Homework Statement A cylinder is pure rolling up an inclined place. It stops momentarily and the rolls back. In what directions is the force of friction directed during the journey? The Attempt at a Solution While going up, the cylinder rotates in the anticlockwise direction, and so the...

So I'm a junior in mathematics and I've reached a point to decide about graduate school. I love pure math and am considering getting a PhD in it. But I do not want to go into academia because I don't think I will enjoy teaching. So I want to go into the industry after a PhD. But one of my...

Can anyone help with how can i become one...Just for hobby..Ive checked out http://hbpms.blogspot.com/ but some guys think that this is overkill so maybe anyone can help me with this...

By "physical particle" I mean color-singlet particles which have asymptotic T=\pm \infty states. How many stable particles exist in the theory? Only one? SU(2), SU(3), and SU(N) gauge groups can all be discussed.

Hi, Just wanted to know if any of you guys had any useful advice with regards to careers from a maths degree. I am in my second year of a integrated masters (in the UK) and would be open to further study. I am doing well academically so far (top 15% of my uni, which is prob 2nd best in UK)...

I know that the vapor pressure of a solvent would decrease with a changing concentration if there was an addition of a solute. However, would the vapor pressure change with a changing concentration of the pure solvent (no solute added)?

Homework Statement The activity coefficient of zinc in liquid brass is given (in joules) by the following equation for temperatures 1000-1500 K: RT ln γZn = -38,300 x2Cu where xCu is the mole fraction of copper. Calculate the partial pressure of pure zinc PZn over a solution of 60 mol%...

Homework Statement Solubility of acetanilide in water is 5.5g/100mL at 100C 0.53g/100mL at 0C A 0.150g sample of acetanilide containing only traces of impurities was recrystalized using a total of 3mL of hot water. a) What is the maximum possible percent recovery of pure acetanilide...