Negative Definition and 1000 Threads

What is the "first positive", "second positive", "first negative" systems of nitrogen Hello, I have been trying to catch up on spectroscopy theory, and I'm trying to get a grasp on what all the terms mean. I constantly seem the terms "first positive system", etc... coming up, and I'm not sure...

Does anyone know if I run 12 volts dc at 1 amp power for a distance of 250 feet and one wire is 12 gauge used for positive and other negative wire is 20 gauge will the smaller ground wire affect what the positive wire can carry? John

In the Klein-Gordon equation (spin 0), the mass dependence is (only) through m^2, whereas in the Dirac equation (spin 1/2) it's through m. Does this mean that for spin 0 particles, we can just as well describe them as having negative mass without changing any of the physics (whereas for the...

I accelerate a mass upward by 2G (2×force of gravity) over some change in height Δh_{1}, then I apply only \frac{1}{2}G over some other change in height Δh_{2}. If, over Δh_{2}, the mass still moving upward (but accelerating downwards), am I doing positive work over Δh_{2} even though the mass...

Energy -- Can energy be negative? Can energy be negative? If yes,can mass be negative?(since E=mc^2)

I think this is one of those papers that will have millions of citations http://arxiv.org/abs/1205.3807 Accelerated Expansion from Negative Λ James B. Hartle, S. W. Hawking, Thomas Hertog (Submitted on 16 May 2012) Wave functions specifying a quantum state of the universe must satisfy...

Hey all, I'm trying to solve a problem in which I have a uniaxial (uniform in two directions, different in the other) crystal with the optical axis normal to the plane of reflection. I call the permittivity parallel to the optical axis ε_par and the permittivity in the other two directions...

Let \begin{equation*} A=% \begin{bmatrix} 0 & 1 & \cdots & n-1 & n \\ 1 & 0 & \cdots & n-2 & n-1 \\ \vdots & \vdots & \ddots & \vdots & \vdots \\ n-1 & n-2 & \cdots & 0 & 1 \\ n& n-2 & \cdots & 1 & 0% \end{bmatrix}% \end{equation*}. How can you prove that det(A)=[(-1)^n][n][2^(n-1)]? Thanks.

Ok, this one's got me stumped! Let's take as an example the probability density function for a random variable X so that: f(x) = \frac{4}{3x^{3}} 1≤x<2 f(x) = \frac{x}{12} 2≤x≤4 f(x) = 0 So the CDF for this variable comes out as: F(x) = \frac{-2}{3x^{2}} 1≤x<2 F(x) =...

I was wondering about a system, specifically quantum, though classical solutions are still welcome, which was resisting all applications of Noether's Theorem, and related techniques. If a system is invariant under a switch from E→-E AND m→-m, then what are the conserved quantities (in analogy to...

Hi! Homework Statement 1. Substituting an ansatz \Psi(x)= u(p) e^{(-i/h) xp} into the Dirac equation and using \{\gamma^i,\gamma^j\} = 2 g^{ij}, show that the Dirac equation has both positive-energy and negative-energy solutions. Which are the allowed values of energy? 2. Starting...

Hi this is my first subject in this forum and i hope you can help 1.we have been given an assignment to analyze this non-ideal op amp with both positive and negative feedback and to be honest i don't even know where to start i know i should post an attempt of trying to solve but honestly...

I'd like to know how do i find I2 (Negative sequence current) if I know Ia, Ib and Ic but don't know angle (in normal system_not fault)? My system's 3 phases 3 wires.

I built a clock generator using a 555 and I fed the output to a high pass filter. It works for the most part, BUT the input voltage ranges from 0 to 5V while the output is -5 to 0 V. I can't figure out why this is happening. I'm new to EE, so bear with me.

Who first assigned "negative" to electrons and "positive" to protons? a sort of history question... the fact that the actual flow of charge (which are electrons in metal conductors) is in the opposite direction of the "positive" current flow in circuits has always been an annoyance to me...

I just completed a problem regarding a Millikan Oil Drop Experiment. I ended up with a negative voltage in the solution. I am just trying to understand negative voltage. Does it mean that the current will travel from - to + instead of the conventional + to -?

Hi there, Please help :) out of school for years started studying again and finding it so hard to pick up the basics again! But am trying very hard! Homework Statement Simplify the expression and eliminate any negative exponents Homework Equations (2x^3)^-2 (3x^4)^2...

if electricity is flow of electrons and also positive and negative charges attract then why electricity needs a conducting medium. electrons has mass and it should just travel through vaccum then why in vacuum electricity cann't travel please reply!

I'm studying for an exam and I'm struggling to understand op amps, here's my problem: I understand that for an op amp to have a controllable gain, the difference between the input terminals must be very very close to zero (and you can assume it is zero). And to do this you use negative...

Find the sum of e^(-nt) as n = 0,1,2,3,... Apparently it's 1/(1-e^-t) Can't use normal geometric series formula though as if a =1, r = e? Any ideas Thanks :)

If resting potential is negative, then K+ ions shouldn't be passively exiting the cell. It doesn't make sense for a male that is attracted to females to leave a club full of females and go outside where there are lots of males. There are females to be had!

The reaction between sodium carbonate and calcium chloride gives the table salt and calcium carbonate. The reaction takes place immediately after mixing two solutions. Can anyone suggest me how the reaction can be slowed down? Thank in advance Peace Deb

Homework Statement The question is to find sin 2x, cos 2x, tan 2x from the given information: sin x = -\frac{3}{5}, x in Quadrant III Homework Equations Half Angle Identities cos2x = cos^{2}x - sin^{2}x sin2x = 2sinxcosx tan2x = \frac{2tanx}{2-tan^{2}x} The Attempt at a...

Hello, Second term of a geometric series is 48 and the fourth term is 3... Show that one possible value for the common ratio, r, of the series is -1/4 and state the other value. ar=48, ar^3= 3... so ar^3/ar=3/48 which simplifies to r^2 = 1/16, therefore r = 1/4 Can anyone explain where...

Homework Statement see attachment Homework Equations The Attempt at a Solution Do you see the step where they go from (1.35keq2)/a2 to 1.91keq2)/a2 ? I can't get that step. To my mind. If you square 1.35 then take its square root, you get 1.35 not 1.91

What is the difference between decreasing acceleration, deceleration and negative acceleration? Most importantly, i want to clarify that acceleration is the rate of change of velocity over time, it Does not necessarily mean that the car velocity is increasing and that a car is speeding up when...

Homework Statement The Clausius inequality combined with the defintion of entropy yields an inequality known as the increase of entropy principal, expressed as Sgen ≥ 0 where Sgen is the entropy generated during a process. Homework Equations Sgen ≥ 0 The Attempt at a Solution...

Ummm. Let me think.

Can the spring constant "k" be negative ? Hi, I found a difficulty when solving this problem from my textbook : In the arrangement of Figure 7-11 (which is basically a standard block attached to spring resting horizontally), we gradually pull the block from x = 0 to x = +3.0 cm, where it is...

If the positive energy is the capacity to perform work what about the negative energy?

Hi Just wanted to know if negative frequency has any significance? Thanks Salil

I started wondering about this after solving a problem on the exam. Here is the problem: 2 planes has a speed v1 and v2. They are flying from the airport at the same time. The difference between their landings on the same airport is t. Express the distance between the airports as functions of...

Dear all, I'm facing a problem in performing incomplete Cholesky decomposition of sparse matrices. I use the algorithm which avoids talking square roots, given in here: http://en.wikipedia.org/wiki/Cholesky_decomposition and apply it to sparse matrices by just skipping the zeros ( no...

Consider an op-amp in which there is a DC voltage of 100mV for example applied to the non-inverting (positive) terminal of the op-amp and the negative terminal of the op-amp is connected to the output directly. Also take the voltage supplied to power the op-amp, Vcc, to be 15V and the gain, A...

Red is for + and Black is for -. If I place red rod into positive side of battery and place black rod into negative side of battery, it displays +9V. If my hand is touching the black rod, and the red rod is touching the ground, then it displays a negative value, I would like to know...

I'm kind of struggling with the concept of energy. A particle in a conservative field has kinetic and potential energy (E=T+U), but I can always choose an inertial frame where the motion of the particle is zero, which means I can change the the particle's kinetic energy by just switching frames...

Probably the stupidest question I have ever asked, but is it possible to prove that the multiplication of two negatives yields a positive? Go easy on me I've asked better questions :D BiP

hi, why are the energy levels of electrons in say a hydrogen atom -13.6ev, -3.4 eV etc ? i thought energy is always positive? what does the negative mean? thanks!

Do tensile testing machines reduce the value of load in these regions? If yes, why? If no, what's happening in the graph?

hey friend can anybody give answer? why (-) * (-) = (+)

When taking about potential and electric field, potential difference is equal to the negative of the area under the graph of E vs distance? why is that. My book defines it as the negative integral of Force times ds or V(intitial) - area under the curve. I don't understand why it's negative. I...

Homework Statement Trying to work out final velocity of a projectile that is initially fired at a negative angle. Initial velocity is 30m/s at a negative angle of 16 degrees. Initial height is 0.44m. Can't get my head around the initial horizontal velocity. I figure its Vox =30 sin 16...

In lorentz transformation, why has t -sign

Homework Statement there is an equation: 2^x=-6 Homework Equations The Attempt at a Solution I know that log need to be used to find x. but I can't find the log of a negative number,,

2 unit negative chargees and a positive charge +q are along the same line. what should be the magnitude of charge q and in which position must it be placed so that the three charges remain in equilibrium...

silicon has a negative temperature coefficient of resistivity. So that means that it's resistivity decreases as temperature increases. How is that possible? Also, would that mean that at some certain temperature higher than room temp, silicon would act as superconductor? It has a very high...

I've been doing this online math bridging course from a German uni to which I am planning to go soon, it is going through all high school maths from the beginning(it has been a while since I did it). The chapter on roots so far ignores complex numbers, which will be introduced in a later...

If you integrate 1/(1-y)dy why do you end up with a negative in front of your answer -ln|1-y|+c

Homework Statement Solve \sqrt{-e^{(i2\pi)/3}} Homework Equations The Attempt at a Solution I seem to be missing something simple, as I take: \sqrt{-1} = i then, e^{(1/2)*(i2\pi)/3} which comes out as: ie^{i\pi/3} however, the solution is: -ie^{i\pi/3}, and I can't seem to see where...

Homework Statement See attachment Homework Equations The Attempt at a Solution Why is it -umg(50)? Why negative? Also I think this has something to do with conservative force and friction, and I'm very confused on this. Any help would be appreciated thanks.