Correction Definition and 178 Threads

Could anybody explain me why indeed we can express the first-order correction to the n-th wave function \psi_{n}^{1} by linear combination \sum_{m} c_{m}^{(n)}\psi_{m}^{o}

Hope I'm in the right section for this question! In the big bang model, the expansion of the universe is slowed down by gravity. If there is enough matter in the universe, then the expansion can be overcome and the universe will collapse in the future. The density of matter that is just...

Homework Statement find series expansion of relativistic energy formula, At what speed is there a 10% correlation to the non relativistic KE. Homework Equations $$ E=\frac{mc^2}{\sqrt(1- \frac{v^2}{c^2})} = mc^2 + \frac{1}{2}mv^2 + ... $$ The Attempt at a Solution I found the series above...

Typically the power factor penalty that a utility charges is only for inductive lagging power factors or leading ones too? i.e. is the penalty for all PF differences from unity or only on the inductive side? e.g. Say I have a lot of motors which bring the PF down & I add a static capacitor...

Hello everyone; My question is regarding to velocity effect on transducer diaphragm. When fluid flow is acting to differential pressure transducer's diaphragm, the diaphragm is osculating(vibrating) and there will be fluid flow which is transverse(opposite flow,back flow) to normal fluid flow...

I have been reading about it a lot, but I still cannot grasp the concept and procedure of Atmospheric Correction. If, for example, a have a raw image from a satellite, how does Atmospheric Correction do its processes, and what would be the expected resulting image?

I considered a free falling object in the Schwarzschild metric at rest at infinity and found as approximation the acceleration : $$\frac{d^2 r}{dt^2}\approx -\frac{GM}{r^2}+\frac{3G^2M^2}{r^3c^2}$$ This would mean if there are no sign error in some sense that the force becomes repulsive at...

Hello there, I've been given the relativistic correction of the Schrödinger equation for a free particle: $$ - \frac{\hbar^2}{2m} \frac{\partial ^2\Psi}{\partial x^2} - \frac{\hbar^4}{8m^3c^2} \frac{\partial ^4\Psi}{\partial x^4} + E_0 \Psi = i \hbar \frac{\partial \Psi}{\partial t} $$ How we...

The configuration and dimensions of any experiment are important in determining wave amplitudes. Then why are the orientations of complex waves not considered when they are added? For example in two dimensions; To find a resulting wave at a point P1 from two paths R1 & R2 we have...

Hello... kindly help me out in designing of power capacitor to improve the power factor as the given load is 950 KWatt and power factor is 0.7, as i want to improve the power factor to 0.92 then what formula i should use to design the capacitor as the Voltage line to line are 400Volts

< Mentor Note -- thread moved to HH from the technical engineering forums, so no HH Template is shown >[/color] Hi there. I am wondering if someone can help me.. Below is a question and answer, I need help with IV . Where does the 0.51 and 0.28 come from? I've tried cos and sin and thitha but...

Hi all, I'd like to ask how to draw the penguin diagram of b -> s gamma process with FeynArts ? It's the diagram at: http://inspirehep.net/record/832732/plots S.

The corrections to the energy per electron in a jellium model (uniform distribution of positive ion charge approximation to the regulated long range order ionic array) is given by (in units of Ry) $$E/N = \frac{2.21}{(r_s/a_o)^2} - \frac{0.916}{(r_s/a_o)} + 0.0622 \ln (r_s/a_o) - 0.096 +...

In first order correction of wavefunction, |ψ(1)n>=∑ψ(0)m<ψ(0)m|V|ψ(0)n>/(E(0)n−E(0)m) when any two of the original states degenerate, we replace the two states with their corresponding "good states" to get a new set of "undisturbed" states (ψ(0)m), AND then we determine the first order...

Hello In Special (and General) Relativity, has a physical (real) clock corrections, with respect to an ideal (mathematical) clock? For example, the physical clock has mass, so it will affect its own measure. This is only an example I thought, I don't know if there are more corrections...

I've no idea if I should be posting this here or in the general forums. This is not really an exercise as much as an example. I'm not understanding something though: 1. Homework Statement Using perturbation theory, find the exact expression for the energy given by the hamiltonian...

Hi there, I'm not sure if someone here can help me because the topic is quite specific. In LDA+U Calculation one have to substract the Double Counting from the DFT functional. There are two main possibilities to do this: 1.) Around Mean Field (AMF) 2.) Fully Localized Limit (FLL) I...

Hi guys, In the photo is the problem. We set Fb =Fe to show for E then out E into the Voltage equation to get V=vlB. However, if we won;t ignore the gravity force, what is the percent correction? (Note: q =Electron)

Please have a look at the following links: http://www.eaton.com/ecm/groups/public/@pub/@electrical/documents/content/sa02607001e.pdf (Table 3) http://www.electrical-installation.org/enwiki/Power_factor_correction_of_induction_motors FigL24) - For power factor correction, why would the...

Hi, I have some questions regarding Kinematics: 1. If an object is accelerating at 9.8 m/s^2, how much time does it Need to reach ten percent of the Speed of light? Speed of light: 299 792 458 m / s -> 10% -> 299 792 45,8 m / s t = v/a -> 299 792 45,8 m / s / 9.8 m/s^2 = 3 059...

For hydrogen atoms, all book take correction up to 1/c^2 where the perturbation is -P^4/8*m^3*c^2. And they go solving it by sandwiching p^4 term where they consider p^2 = 2m*(1+e^2/r). and they square it to solve for p^4. To get a better view of perturbation to first order please see...

I'm brushing up on calculus. I don't see how this derivative works. x(t) = A cos(ωt - \varphi) v(t) = dx / dt = - Aωsin(ωt + \varphi) I get that the derivative of cosx is -sinx. I get that the omega is brought outside the cos function because of U substitution. Why does the the...

Homework Statement A small industry operates from 220 volts supplied by a utility. The small industry represents a load to the utility that represents 22,000 watts and a power factor of 0.8.Determine the value of a capacitor placed at main voltage panel to correct the circuit to unity power...

Hi. I would like to ask a question about Chapter 15 in Srednicki's QFT book. In chapter 15, after eq. (15.12), he compares eq. (15.12) ## \mathrm{Im}\bm{\Delta}(k^2)=\frac{\mathrm{Im}\Pi (k^2)}{(k^2+m^2-\mathrm{Re}\Pi (k^2))^2 + (\mathrm{Im}\Pi (k^2))^2}## with eq. (15.8)...

Hi I have discovered that the Von Neumann bias correction method only works when the bias is 100% stable, for example tossing the same loaded coin again and again. Does anyone know of a bias correction method which can correct an unstable bias? Is this impossible? Edit: Let's say I have a...

Wondering about degrees of freedom. So basically let me express my current understanding: Comparing the statistical errors to the residuals, the former involves taking a subset of observations from a population and comparing them to the population mean, while the latter involves comparing the...

When you connect a capacitor across an inductive load, reactive power (Q) flows back and forth between capacitor and inductor, so (ideally) the generator doesn't need to supply Q to the load. My question is, why doesn't the capacitor supply Q to the generator as well? If only a capacitor were...

I am currently a transfer student doing a BA in physics and two minors in business. At this time I cannot change my major unless it is advisable to go back and complete a BS in physics instead of completing a BA. I want to be able to secure my chances of landing a entry level Drilling...

In my class notes, the muon decay width is: \Gamma_\mu=\frac{G^2_F m^5_\mu}{192\pi^3} Yet, in Wikipedia (take that for what it's worth) it says that, once the corrections have been applied, the muon decay width takes the form: \Gamma_\mu=\frac{G^2_F...

The best experimental tests of the general relativity: of frame dragging by Gravity Probe B, use calculations from approximation of GRT, called gravitomagnetism: http://en.wikipedia.org/wiki/Gravitoelectromagnetism It was originally introduced by Oliver Heaviside in 1893 as expansion of...

Ok. The Lande' g-factor is given as g = g_L \frac{J(J+1)-S(S+1)+L(L+1)}{2J(J+1)} + g_s\frac{J(J+1)+S(S+1)-L(L+1)}{2J(J+1)} Most sources say that g_L = 1 exactly, but Bethe and Salpeter p214 seems to indicate that there should be a correction for reduced mass. g_L = 1- \frac{m_e}{m_i} Is...

Hi I am studying qft with worldwidely used text, written by Peskin and Schroeder, An introduction to qft. I have trouble with the calculation of thr numerator on pp. 192. I got additional term ## 2m(z-xy)(mγ^μ - p^μ) ## between spinors, which seems not vanishing. Is there any idea to treat this...

The problem statement Using the nomogram of FIGURE 10, calculate the size of capacitor bank to give a final power factor of 0.95 for a single phase, 230 V, 50 Hz lighting installation which has a load current of 17.5 A and operates at 0.8 pf. The nonogram gives a value k = 0.44...

Homework Statement Hi, I'm an electrical engineering degree student from Perlis University, Malaysia (UniMAP) and I'm currently doing a Final Year Project. The title is Active Power Factor Correction. I'm evaluating a Boost APFC Board from STMicroelectronics model EVL6562A-TM-80W. The problem...

Homework Statement In general, I know that you can use the equation ωn=[k/m]^0.5 to calculate the natural frequency of a hanging spring and mass system. However, for a non-ideal spring (where the mass of the spring isn't negligible) a correction factor is added to the equation and it...

Knowing the dielectric constant of a medium we can earn the electric field at any point in that medium which is deferent from the applied external electric field. So why do we use the Local field correction?

Homework Statement Homework Equations E_{1}=<ψ_{1}|V(r)|ψ_{1}> The Attempt at a Solution That is equal to the integral ∫ψVψd^3r So I'll just perform the integral, correct ? But r is not constant here right? So, I' ll keep it inside the integral? How should I continue? Please...

Hi guys, I cannot understand why we need to correct cosray intensity with pressure and why the equation that describes the phenomenon is I=Io*exp(-a(Δp))? I want to know the phsyical meaning of this(i assume,experimental) result... Thank you...

Hi everyone, So I'm a bit stuck in my physics lab report. I have to make a correction to the temperature read in the laboratory (ex:155.2C) because our room pressure was 742.1mmHg and not 760mmHg I'm guessing. I've tried researching this for a while now but I can't seem to find an easy...

Is this equation correct? equation 1: mass=density(density-density) Im asking this because in air correction we have equation 2: mass=density(density-density)/density(density-density) -----here we get mass.But get we mass still in this case?:mass=density(density-density) Because I was trying to...

Homework Statement http://i1226.photobucket.com/albums/ee410/jean28x/8b1ad092d9dd25a8f10f1672c0073d97.jpg Vs = 480<0 rms. P1 105 W; pf1 0.7 lagging; P2 5 × 104 W; pf2 0.95 leading. Homework Equations S = sqrt(P^2 + Q^2), = Vrms* Irms(conjugate)The Attempt at a Solution I know how to...

Parallax is a way of measuring the distance of one object to another. By taking the distance of an already known object, say the Sun, and drawing a line to the object. Then drawing another line between you and the object in question. The angle you get is the Horizontal Parallax angle...

I want to know about relativistic correction to perturbation. I searched but failed to find any teaching on this topic. Is it true that we just need to replace the non-relativistic Hamiltonian perturbation terms with the relativistic ones while leaving the perturbation formulae unchanged...

Homework Statement Consider this circuit. Calculate the complex power for the circuit, and correct the power factor to unity by connecting a parallel reactance to the load. Homework Equations The Attempt at a Solution My attempt: Can someone check? Thanks a lot!

I couldn't understand the pressure we take here is still the ideal pressure then wt is the correction made?

I am using arduino and accelerometer MMA7341 to measure the acceleration in x direction of an oscillating metal table. But the mounting of the accelerometer is tilted by a small angle (say Q) . Is it affect the acceleration?. If it is affect the acceleration in x direction , how can correct it...

Hi Guys- So, I'm new to the Power Quality world but have worked in the VFD world for some years. The term "KVARS or VARS" is new to me. Looking for a simple explanation and how they work in a system. Thanks!

Please read the italic part at the top of https://www.physicsforums.com/showthread.php?t=243852 Is it true if we generalize to the complex case that an angle preserving transformation's eigenvalues are all the same magnitude? Is there a simple proof for the real case? Obviously its not a...

I am new at this energy management stuff: My question is, we have a new Central chiller plant where I work that feeds 5 buildings for there A/C. The Power factor at this building is 99% when the chillers are running (outside temp above 50 degrees) but when the chillers are not running the...

Hi I've been meaning to find a correction method for the true location of the sun so when I add the correction to the true sun it would give me the apparent sun. To clarify, I want to be able to calculate the difference of time between sunsets or sunrises if: There were no geographical...