Shift Definition and 653 Threads

Shift work is an employment practice designed to make use of, or provide service across, all 24 hours of the clock each day of the week (often abbreviated as 24/7). The practice typically sees the day divided into shifts, set periods of time during which different groups of workers perform their duties. The term "shift work" includes both long-term night shifts and work schedules in which employees change or rotate shifts.In medicine and epidemiology, shift work is considered a risk factor for some health problems in some individuals, as disruption to circadian rhythms may increase the probability of developing cardiovascular disease, cognitive impairment, diabetes, and obesity, among other conditions.

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  1. E

    Phase Shift of Reflected Wave in Conductive Material

    Homework Statement An EM wave normally shed on a conductive material (\tilde{\epsilon}=\epsilon+i\epsilon_i,\mu_0). Calculate the phase shift of the electric field of the reflected wave relative to that of the incident wave. Homework Equations...
  2. F

    Relativistic transverse doppler shift

    Hi, I was looking up the formula for this on wikipedia and it said that the frequency shift is: \frac{\sqrt{1 - v^2/c^2}}{1+\frac{v}{c}\cos{\theta}} In the case where the the emitter is directly above the observer when the photon arrives it says it simplifies to: \gamma =...
  3. skate_nerd

    Question about doppler shift in relativity

    I've got a somewhat simple question, and I think its from me overlooking something stupid...but how does using doppler shift work if in any moving rest frame the speed of light is supposed to stay at 3(10^8) m/s? I know that E=hc/λ, so for the wavelength of the light λ to change, the only thing...
  4. J

    Is there a phase shift associated with twisted nematic LCDs?

    Hello, As it says in the title, I would like to know if the light entering a twisted nematic liquid crystal display experiences any kind of phase shift specifically when applying a voltage to manipulate the polarisation of the light. If it is the case, could someone point me towards any...
  5. M

    Eigenfunction of all shift operators

    Prove that if a continuous function e\left( x \right) on \mathbb{R} is eigenfunction of all shift operators, i.e. e\left( x+t \right) = \lambda_t e\left( x \right) for all x and t and some constants \lambda_t , then it is an exponential function, i.e. e\left( x \right)= Ce^{ax} for some...
  6. L

    Doppler shift of object in expanding universe

    Homework Statement What's the doppler shift (Δf) of the object moving away from us if we measure a wavelength of light λ=1.55μm emitted from it and it's at a distance of 10 megaparsecs? And is the object red or blue shifted? Added information to the problem is for each megaparsec the object...
  7. T

    Shift in Mercury's Perihelion by finite light speed

    Someone published a simple computation of the relativistic shift in Mercury's perihelion (over and above classical, ie. the small correction over the classical-mechanical shift) by more or less using the principle of relativity. I believe it was a she and she computed how far mercury travels...
  8. rajeshputta

    ACphase angle shift circuit help me

    Dear sir, Iam looking for hard ware support design circuit for AC phase angle shift as per our desiered degree level, For that any circuits is available ?, or we go for coustamized design? Help me. Rajesh.p
  9. F

    But, as a webpage title: Wave Problem: Solving for Phase Shift

    Homework Statement 1. A signal of the form x(t) = A cos(ω0t + φ) is plotted below. From the plot, deduce the following: (a) the amplitude A, (b) the period T0, (c) the radian frequency ω0, and (d) the phase φ in radians. For part (e), find f0 in Hz by converting the radian frequency from part...
  10. A

    Half-silvered rear surface phase shift

    I have read that the rear surface reflection of a half-silvered mirror undergoes no phase shift. But they caution that this is true only for a dielectric mirror. What is the answer for a metallized mirror? It seems to me that the answer must either be 180 degr., or pass continuously to 180 degr...
  11. N

    Pseudo frequency? Related to phase shift

    I am reading a text about how MRI works and I came across a thing that I am totally confused. The book mentions about that few particles side by side with their nuclei spinning at the same frequency but they all have a phase difference. Since MRI cannot measure the phase differences directly...
  12. D

    Energy Change Due to Doppler Shift

    Hello all, so let's suppose a photon is being gravitationally red or blue shifted changing its frequency which ultimately changes its energy, where does this energy change come from?
  13. L

    How and how much does is the cosmological red shift affected?

    When we look out into deep space we see a red shift in the light from distant sources because they are more or less all receding from us. How is the red shift distorted by passing through our local galactic gravitational well, before hitting us down here on the ground?(more red/more blue/no...
  14. G

    Doppler shift with 2 trombones

    Homework Statement Mary is blowing her trombone at 400hz. Paul is approaching her at speed v, blowing the same type of trombone. These trombones has a maximum frequency of 500hz. What is the maximum speed Paul can approach Mary, and still cancel out her trombone noise? Homework...
  15. Solarmew

    Is the Relativistic Doppler Shift Formula Correctly Applied in this Problem?

    I was just wondering if this problem is right and I'm missing something or ... http://www.astronomy.ohio-state.edu/~ryden/ast143/ps3_soln.pdf Cuz I'm reading the GRE book and it says here to use the relativistic Doppler shift formula. So the problem in the link would need to be solved like...
  16. C

    Dark energy acceleration of space effect on red shift

    I have not seen this discussed so this a question in the form of a statement for clarity. If light left a star 10 billion years ago and space has expanded for 10 billion years before the light is observed the light frequency would be stretched out or red shifted therefore some of the red...
  17. 7

    Manipulating a formula for a relativistic Doppeler shift

    Homework Statement The spaceship is approaching Earth with a speed ##\scriptsize 0.6c## under an angle of ##\scriptsize 30^\circ##. What frequency does an observer on Earth measure if spaceship is sending frequency ##\scriptsize 1.00\cdot10^9Hz##. Homework Equations Lets say we take the...
  18. L

    Transformation question; first order shift of a scalar field

    Hi to all! I have the following transformation \tau \to \tau' = f(\tau) = t - \xi(\tau). Also I have the action S = \frac{1}{2} \int d\tau ( e^{-1} \dot{X}^2 - m^2e) where e = e(\tau) . Then in the BBS String book it says that $$ {X^{\mu}}' ({\tau}') = X^{\mu}(\tau)$$ and...
  19. Y

    What is scalar voltage potential with phase shift means?

    Say ##V_{out}=4e^{j\frac {\pi}{6}}##, what is this mean? It is a scalar voltage. Does this means: 4e^{j\frac {\pi}{6}}=4\left(\cos \frac {\pi}{6}+j\sin \frac {\pi}{6}\right) = 4(0.866+j0.5) = 3.4641+j2=4\angle 30^o What is the phase shift means, reference to input? Thanks
  20. W

    Has anyone experimentally measured the Lamb shift in Antihydrogen?

    I could only find abstracts for proposals of methods that could accomplish this. I don't have any subscriptions to journals so I can't read the papers. Also while I'm on the subject, the energy levels of antihydrogen should be the same as hydrogen right?
  21. R

    Doppler Shift/ Doppler effect HELP

    Doppler Shift/ Doppler effect! HELP 1. A police car is traveling at a constant speed of 110. km/h with a radar gun which generates and detects radiowaves. The police car and the ambulance drive directly towards each other. The radar gun produces radiowaves with a wavelength of 0.0440 m. An...
  22. H

    Redshift of Light: Exploring Possibilities of the Big Bang

    I have long been curious as to the Big Bang. Our cosmology is based on Hubble's observation of the red-shift and its interpretation, and our observations are made to fit the interpretation of an expanding universe. What if simply the frequency of electromagnetic radiation decays (lengthens) with...
  23. B

    Doppler shift, c, observation, recession, spacetime expansion

    Hi all, It is my understanding that a Doppler shift is the result of a change in wave frequency due to a change in distance of a signal source, relative to the observer. I assume that the change in distance must be continuous, in order to observe a Doppler effect: frequency increase =...
  24. E

    Energy shift in a photon passing by a gravitational well

    Gravity effects the energy of a photon per the equation GM/c^2r. I understand that a photon traveling on a crash course with a black hole will be blue shifted according to the hole's mass, however I'm a little confused as to what happens when a photon simply passes nearby a massive object. For...
  25. bitznbitez

    Differentiating Redshift Type by Spectral Shift Signatures

    Spectral redshift is currently understood to be of a variety of sources, velocity / doppler redshift, gravitational redshift, cosmological redshift, etc. Is there any ability to tell,purely from the spectral analysis of the light itself, without knowing what the source of the light is, what...
  26. J

    Phase shift and amplitude change when put through FIR filter

    Hey all, I am having trouble with this problem: A sampled sinusoidal signal having a normalized frequency of 0.30π is sent through an FIR filter. The filter impulse response is, h[n] = 1/3δ[n] + 1/3δ[n-1] + 1/3δ[n-2] From this I must find out by what factor the input signal is...
  27. N

    Mass Increase and Distances: Red Shift or Blue Shift?

    In a hypothetical universe where mass of matter constantly increases, will we observe that distances also constantly increase? This is not a new theory, I'm just asking what classic GM says about that. If we are in a galaxy with constantly increasing mass, measuring distances to other...
  28. N

    How Does the Shift of Charge Occur in CCDs?

    Hello everybody, All resources I found online about CCDs, state that they shift charge one step at a time. How does this shift take place? Thanks
  29. A

    High-Energy Doppler Shift & Pair Production

    Hi all, Let's say you are at rest with respect to the galaxy, and you have low energy photons all around you. Now, if I crank my energies up relatvisitcally, the frequency and thus E = hf of those photons will increase. Red Light becomes Blue Light, Blue Light becomes UV, UV to X-ray, and...
  30. L

    Archived Optics: Shift in y from a thin pane of glass, young's experiment.

    Homework Statement With regard to Young’s Experiment, derive a general expression for the shift in the vertical position of the mth maximum as a result of placing a thin parallel sheet of glass of index n and thickness d directly over one of the slits. Identify your assumptions. Homework...
  31. J

    What is Einsteins Paradigm Shift?

    A search for the term "Paradigm Shift" brings up a definition and a list of examples including Einsteins Relativity. What is it, exactly, about Relativity that constitutes a paradigm shift? JM
  32. A

    B Gravitational red shift and gravitational time dilation

    How does the gravitational red shift causes time dilation?
  33. N

    Doppler Shift Special Relativity Question

    Homework Statement light signal of frequency 33 MHz is reflected off a (radio)mirror that is moving toward you at half the speed of light. What is the reflected frequency in Hz?Homework Equations f_f = f*sqrt((1-v/c)/(1+v/c)The Attempt at a Solution The mirror and light wave are approaching...
  34. A

    2D Doppler Shift / Relative Velocities

    Hi, I'm trying to adapt the doppler shift formula for a stationary listener and a source traveling in a straight line towards/away from the listener to the case where the source does not move straight towards the listener. For example, suppose that I am looking north and train further in the...
  35. V

    How to find the phase shift and amplitude ratio

    i am looking for the amplitude ratio and phase shift of this graph? could someone explain me how to obtain these results from this type of graph? thank you
  36. G

    Conflicting Transverse Doppler Shift Equations?

    http://en.wikipedia.org/wiki/List_of_relativistic_equations#Doppler_shift and http://www.physics.umanitoba.ca/~souther/waves02/feb0402/sld011.htm If you look at the derivation on Wikipedia: v' = γv But the one on Uni of Manitoba shows: f' = f0(1-β^2)^(1/2) or f' = f/γ...
  37. T

    Question on Red shift applied to objects within the same galaxy

    Hi everyone, I signed up just to ask you guys a quick question, as most of you will know infinitely more than I do on this subject. I'm not an astrophysicist, I have a strong interest in the universe and cosmology, but it's more of a hobby for me than a central focus, so I apologise in...
  38. Q

    What Are the Effects of Zeeman Shift in Positronium?

    Homework Statement The magnetic moment for an electron is \mue = -e/m Se. The magnetic moment for a positron is \mue = +e/m Se. In the ground state, the quantum numbers are n=1 and l=0. a) What is the physical mechanism for the Zeeman shift? b) Write the Hamiltonian and identify H0 and...
  39. F

    Phase shift upon reflection of electromagnetic wave

    I have indirectly sought the answer to this for some time (since I studied an introductory course in optics 'long' ago), but nobody has been able to give a satisfactory answer, and I have not been able to find the exact answer on the Internet either. My question is about optics, and more...
  40. Daaavde

    How precise can Doppler shift be measured in detecting exo-planets?

    As the title says, I'm interested in the precision a Doppler shift can be revealed. That's why I read that it's possible to detect exo-planets by measuring the Doppler shift of the star's spectra. Works like this: the stars moves, since it moves back and forth is spectrum suffer from Doppler...
  41. S

    F = MA 2010 Exam # 24 (MoI after shift in CoG)

    Homework Statement http://www.aapt.org/physicsteam/2010/upload/2010_FmaSolutions.pdf See Number 24Homework Equations CoM = M1x1 + M2x2 / (M1+M2) MOI_disk: 1/2mr^2 The Attempt at a Solution So what I was thinking was find the new CoM then use the parallel-axis theorem. To find the new CoM: MsXs...
  42. M

    How do you finish rearranging the Doppler shift formula

    Homework Statement i am using the Doppler shift formula Fs=F0(1/1+-(vsource/c) i can rearrange it to an extent but when i use it to find my answer i i need to divide it by two in order to do it, every time. I would just like to understand why this is, or if i am doing it completely wrong...
  43. Mordred

    Entanglement/event horizon red/blue shift

    Heres the scenario 2 entangled particles one sent to an event Horizon due to the increase in gravity it will blue shift. The other particle at the same time is sent in the opposite direction. For purpose of this let's say that the force of gravity is simultaneously reducing. In a manner that...
  44. A

    Special Relativity and Blue Shift question

    Earlier today I was on youtube when I saw this comment I went to respond to this saying that the light would blue shift out of the visible spectrum and you wouldn't be able to see anything. But then I thought about time dilation from relativity and wondered if the slowing down of time would be...
  45. N

    Finding velocity of a vehicle using Doppler Shift for sound

    Homework Statement You are standing on the side of the Trans-Canada Highway as the Physicsmobile approaches you. As it approaches, you hear an engine noise of 1100 Hz. After it passes, you hear an engine noise of 950 Hz. How fast was the Physicsmobile travelling? Homework Equations...
  46. G

    Compton Shift and energy of scattered x-rays

    X-rays with a wavelength of 0.2x10^-9 m collide with a target. The scattered X-rays experience a Compton shift of 0.0007x10^-9 m. What is the energy of the scattered X-rays?Just wondering what equations I would use here etc? Any help would be much appreciated, thanks.
  47. H

    Fundamental Shift and Scaling of Signals

    Homework Statement I'm confused on whether or not two functions would be equivalent or not. Let's say x(t) is a triangle with height 1, width 1. The hypotenuse of it is the function t (with a slope of 1). I'm told that x((t+2) / 4) then is making it 4 times as wide and left-shifting the...
  48. G

    PLL with adjustable constant phase shift

    I had been wondering if this were possible for a long time. While working on my MS thesis at school, I learned about Phase Locked Loops for the first time. It took me weeks of curling up at night with H.&H. The Art of Electronics for me to even get the concept. I had never heard of a Bode plot...
  49. C

    Gravity shift due to sun & moon passing overhead

    I would like to know a function or at least an approach toward developing a function that describes the change of gravity on the Earth's surface due to the sun, moon and if possible, the tides. I am quite familiar with the fundamentals but my math isn't up to this. Thanks in advance...
  50. B

    Phase Shift vs Phase Shift Keying

    Respected Friends ! I want to know the relationship between Phase Shift (PS) and Phase Shift Keying (PSK). Please can anyone help me. Thank You
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