Phase Definition and 1000 Threads

Folks, It's been a while since I've done calculations like this so I was wondering if someone can help me calculate the volume of a gas at a specific temperature as compared to its liquid volume when measured below its boiling point. I can't seem to find a phase diagram for this material, is...

Hi there. So here goes. I have been having issues with a replacement chiller unit that requires 230VAC single phase. An identical unit was running on 2 phases of a 110VAC 3 phase supply. I had a start capactior fail in this unit. When I connected the replacement unit, the compressor...

Hi! [FONT=HelveticaNeue]Ok, I got another question here. I don't understand how to draw the vectors. This is a method to simplify analysis of unbalanced three-phase power systems but I just don't understand the drawing here. Do you think you can explain how? I understand how to draw the vectors...

Take a look at the attachment, my question is obvious from the colored points. The attachment is from: "state-of-the-art formulas for helicity amplitude calculation and all that (version 2.4) PART Ia. Spherical-Vector Method for Helicity Amplitudes (FORMALISM) Ken-ichi Hikasa" I think...

Hello everyone,can anyone help me to understand the phase congruency principle. I have read that,in image processing if we reconstruct an image using its phase only,we can get obtain edges and lines and this is because of phase congruency principle. I am searching more about phase...

What is phase velocity? I know it is defined as v=ω/κ But what does this phase velocity tells about the wave? Does it means the velocity of wave?

Hello, I know that the latent heat of a first-order isothermal and isobaric phase transition is in general given by the difference in enthalpies between the two phases, but my question is: do you know if there is there a way to estimate its value "from first principles" for the case of a...

I'm having difficulties understanding the role of scattering on phase coherence in the Aharonov Bohm Effect. In particular I am trying to reconcile the following points: Inelastic scattering destroys phase coherence and prevents us to see the Aharonov Bohm Effect. Elastic scattering does...

I want to design a single phase induction motor (1/3 HP,50Hz,220V). I face a problem to design the main dimension of stator and Slot shape and Rotor skew angle . Would you give some idea for design ? or any related book and software ?

https://www.physicsforums.com/showthread.php?p=2881300#post2881300 According to the quoted thread above and according to textbooks and Wikipedia the phase between the E and B fields of an electromagnetic wave propagating in free space is zero. This assertion is based on the Maxwell equations...

I am a Grade 11 student and am working on a physics research about Fraunhofer diffraction. I have 2 very basic questions (maybe kind of unprofessional). Hope someone can help. 1.Suppose a beam of coherent, monochromatic, parallel light penetrates an object, and a diffraction pattern forms on...

Hi All, I have access to a 15kW VFD for little money. I only have single phase 240 vac at home, and need to drive a 10kW motor, 3 phase, 415v. I have been reading that 3 phase input VFDs can be run on single phase, but they must be derated by 50%. This would mean a 20 kW VFD. Also, it is a...

Hi, I'm really stuck on this assignment question and could do with a hand on the step by step process of how to get the answers. A three phase induction motor as 2 poles, a standstill voltage of 121 v/phase (Er), rotor resistance of 0.15Ω/phase (Rr) and a standstill rotor reactance of...

Homework Statement I have an exam coming up and one of the practice questions is as follows A 415V 50Hz three phase supply energises a balanced star-connected load through a three phase feeder with a per-phase series impedance of Zline = ( 0.165 + j0.413 ). A power meter at the source end of...

For a school project I need to be able to shift the phase of a 100 kHz sine wave by 90 degrees (either positive or negative). I have tried several passive integrators and differentiators, both with poor results. I have also tried using an op-amp integrator and differentiator, but in both cases...

Hi I have been trying to find the types of equipment required to protect 3 phase generators+transformers for a while now but I just cannot seem to find anything. If you could help me out and give me examples of the equipment it would be greatly appreciated Thanks

Homework Statement the turntable is rotating at 36.25 rpm. the simple pendulum is performing SHM at 36.00 prm. how many complete oscillations would the pendulum execute so that both are in phase? Homework Equations The Attempt at a Solution my working is 36prm divided by 0.25 rpm...

Homework Statement the question doesn't state that which particle is leading/lagging which particle. Homework Equations The Attempt at a Solution for the first particle, my working is 10 sin(2pi/3 )= 8.66cm for the second paticle, my working is 10 sin(2pi/3+ 30pi/180)= 5 cm...

How to prove that energy travels at group velocity and not phase velocity?

hi everyone,i know that the phase spectrum contains most of the structural information about the image.But i want to know more about importance of phase spectrum related to video signals. I have read that temporal variations of phase values are able to capture most of the dynamical...

Homework Statement An RLC circuit has a resistance of 2.0 kΩ, a capacitance of 8.0 µF, and an inductance of 9.0 H. If the frequency of the alternating current is 4.0/π kHz, what is the phase shift between the current and the voltage? A) -1.6 rad B) -1.5 rad C) 36 rad D)...

Please look at picture. My textbook only gives the answer with -pi as a phase constant. But, since we are at "a switching point" on the unit circle, the sign doesn't really matter. The graphs give the same result whether a positive or negative sign is used. Am I right? Does it conceptually...

I am beginner in image processing and want to do filtering in Frequency domain. I can understand that the frequency spectrum in case of 1D waves. It denotes what frequencies are present in a wave. If we draw the phase spectrum of cos(2πft) , we get an impulse signal at −f and +f, and it is...

So, I'm trying to study phase shift in an unbalanced rotating system (where "phase shift" means the resulting response of orbital motion lags behind in time/position relative to the force that's causing it) I know that conservation of angular momentum applies ideally in a closed system...

I just wanted to check something. If I have a complex number of the form a = C * \exp(i \phi) where C is some non-complex scalar constant. Then the phase of this complex number is simply \phi. Is that correct?

Homework Statement since point P is ahead of point O, why the displacement , y , of P shouldn't be Asin(wt + 2pi/(x)) ? Homework Equations The Attempt at a Solution

Homework Statement I need some help understanding how the phase shift was calculated in the following solved problem: So how did they work out the phase shift to be π? The Attempt at a Solution What formula have they used to find the phase shift? :confused: I couldn't find any notes in...

Hello, Wikipedia states: Phase changes, such as melting or evaporation, are also isothermal processes. I am interested in calculating the enthalpy of a given phase transition. If the process is isothermal, I would immediately say that H is 0, according to the following equation: dH=CpdT...

The solution's form for the ODE $$\frac{d\vec{r}(t)}{dt\;\;\;\;} = k\;\vec{r}(t)$$ can be generalized like in this diagram: https://upload.wikimedia.org/wikipedia/commons/3/35/Phase_plane_nodes.svg Exist some program or some way of adjust some program of math for study the behavior of the...

Homework Statement i can't understand why curve above is for under dampling and the below curve is increased dampling. can someone explain please? https://www.flickr.com/photos/123101228@N03/14296397365/ Homework Equations The Attempt at a Solution

Homework Statement for part ii , why the phase difference isn't =pi/2 ? I'm having problem uploading the photo .https://www.flickr.com/photos/123101228@N03/14289633415/ Homework Equations The Attempt at a Solution

"Precipitation hardening is a heat treatment that distributes secondary phases more evenly in an alloy..." What does it mean by a secondary phase?

My professor, in his handout (picture below), says the following about this diagram : I disagree with him partly. For \Delta_{mix} G/nRT<0 mixing is spontaneous and hence there solutions would be miscible. Hence at \beta=2.5 should we not expect the components to be fully miscible. ...

There is a lecture called fundamentals of electric and electronics and there is a new topic in that lecture I have to learn but I have little information on it. Topic is three phase systems or three phase power calculations or something like that. There are big letter such as R,S which...

Homework Statement 1) If one is using light bulbs to detect phase sequence then it is wise to connect them in series with circuit resistor. Why ? 2) There is short circuit in phase "A". In which case is short circuit voltage larger, in four-drive (?) system or in three-drive (?) system ...

Homework Statement a) Starting from the statement that total entropy (Ssystem+Ssurr) can only increase, show that G = U - TS +pV will attain its minimum value for a system in equilibrium with a fixed pressure and temperature reservoir. b)At atmospheric pressure, a particular substance is...

Homework Statement Part (b): Find the temperature in which the pressure is twice the atmospheric pressure. Homework Equations The Attempt at a Solution I've done every part except part (b). Part (b) \Delta v \approx v_{gas} = \frac{RT}{p m'} Therefore the clausis-clapeyron equation...

What is meant by phase of a wave? I can't get a grasp of it especially after knowing that in an em wave ,the magnetic and electric fields E and B respectively are in phase , aren't they time varying and perpendicular to each other? Doesn't changing the inclination affect the phase ? Also,the...

In classical mechanics we can get a nice overview of the dynamics of a system by looking at its position-momentum phase space. Is there a useful analogue of this concept in special relativity? Can the dynamics of a relativistic system be represented by its phase space in the same way as is done...

I am looking for a way to connect the Condon-Shortley-Wigner to the Edmonds phase convention. Specifically I am writing a program to compute Wigner-d matrix coefficients From tabulated values (e.g. even Wikipedia) d^1/2_{1/2,-1/2}=(-1)^{-1/2-1/2}d^1/2_{-1/2,1/2}=-sin(theta/2) So...

I understand that a local gauge transformation functions to conserve the energy of an electron as it moves through space/time. What I don’t understand is why the energy of the electron, as dictated by the momentum and potential energy terms of the Schrödinger equation changes as a function of...

Homework Statement Given the circuit above. a) Find I1, I2 and I. b) Find the power used in branch 1 and branch 2. (please correct my "translation" if it's wrong) c) Find the resulting impedance and phase angle. (Is resulting impedance a term?) d) Find the voltage between...

HELLO everyone.. i have read some journals and some researchers (not all but most of them) said that bismuth manganate MUST be synthesized in high pressure conditions. in other words, not in room temperature/pressure. it that true? because some of researchers also synthesized that BiMnO3 in...

Given a function of the time like ##f(t)##, its Fourier transform is ##F(\nu)## and by definition, ##Abs(F(\nu))=A(\nu)## and ##Arg(F(\nu)) = \varphi(\nu)##, so I have amplitude and phase as function of the frequency, but make sense speak in amplitude and phase as function of the time? If yes...

Let's use the material brass as an example. My problem is that I have no understanding of the concept of "phases". In the phase diagram for brass, we have α, β, γ, δ, ε, and η phases as well as the liquid phase (L). My question is, how do I interpret these phases? What is the difference...

So I know how polaroids and 0.5λ plates work, but does this mean that the polarization of the light and the phase of light are the same, but that the polarization of light is actually a vector description of light? Or something like that? Are these two the same?

Question: A) Explain what happens when a gas is kept in a cylinder under constant pressure while being cooled. Assume that constant pressure is less than critical pressure. Draw PT and VT diagrams for this? B) Describe and explain what is seen when a strong transparent container of constant...

Q: How do you find the phase between an input and output signal? These signals are swept-sin (chirp: https://en.wikipedia.org/wiki/File:Linear-chirp.svg) signals for system identification, so I'm looking to find a transfer function. Background: A frequency-domain Transfer Function's magnitude...

The Sun about 4.5 billion years old and in about another billion years will have used up the hydrogen particles in its core and will have to use the ones closer to its surface which will make the sun's surface hotter and possibly make Earth impossible to sustain life. When the sun reaches its...

Hi, Why won't a generator composed of a stator that has 9 coils (each connected to it's neighbour in a ring until line out), and a rotor that has 10 permanent n50 magnets (NSNS...) generate useable electricity?