What is Shift: Definition and 653 Discussions

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. R

    Perturbation Theory energy shift

    Homework Statement I'm trying to calculate the energy shift given an electron in a 1D harmonic potential has a wavefunction \Psi_{0}(x) = \left(\frac{m\omega}{\pi\hbar}\right)^{1/4}exp\left(\frac{-m\omega x^{2}}{2\hbar}\right) The shift in E_{0} = \frac{\hbar\omega}{2} = 2eV due to...
  2. G

    Relativistic Doppler shift Problem

    A distant galaxy is moving away from us at a speed of 1.85x10^7m/s. Starting from the formula for the doppler shifted frequency, derive a formula for the change in wavelength and hence calculate the fractional redshift (λ'-λ₀)/λ₀ in the light from the galaxy. I'm pretty confused at the moment...
  3. wolram

    Measuring Red Shift to Confirm Hubble Flow

    Over a period of several years could the red shift of some ideal body be used to confirm the Hubble flow?
  4. C

    Doppler shift above speed of sound.

    Homework Statement A source and an observer are each traveling at 0.52 times the speed of sound. The source emits sound waves at 1.2 kHz. (a) Find the observed frequency (in kHz) if the source and observer are moving toward each other. (b) Find the observed frequency (in Hz) if the...
  5. B

    I developing a theory of a general shift function sequence transform

    I need help developing a theory of a general "shift function sequence transform" I'm new here and this is my first post. In 1999 I read part of "The Book of Numbers" by John Conway and Richard Guy and came across a section titled "Jackson's difference fans". In their book, there's no mention...
  6. M

    With moving source, power shift?

    When the source is moving with respect to the observer, the emitted wave undergoes this well-known frequency shift (Doppler shift). But isn't there also a power shift? Let a source emit a signal (sound or light) with constant power, say P_0, and moves towards the observer with constant speed...
  7. N

    Can a 250 cc Honda Engine Be Integrated into a Car with a Button Gear Shift?

    I've a gearbox from a 250 cc Honda engine. The pattern in one down and four up. This engine will be integrated into a car, so the changing of gears will be difficult with the foot pedal. wouldn't it ? :) . So i decided to integrate a small motor to the gear shift pedal so that it can change...
  8. A

    Verilog arithmetic shift implementation.

    Here's my verilog code first of all module arithmetic_shift(input_num, op, shift_num, result); input [7:0] input_num; input [2:0] shift_num; input op; output reg [7:0] result; always @ (*) case(op) 0 : result = input_num <<< shift_num; 1 : result = input_num...
  9. C

    Calculating Truck Speed from Frequency Shift

    Homework Statement You are standing by the roadside as a truck approaches, and you measure the dominant frequency of the truck noise at 1100 Hz. As the truck passes, the frequency drops to 950 Hz. What is the truck's speed? Homework Equations f'= f (vsound)...
  10. G

    Photon Energy vs. Red Shift, Inflation Theory, Acceleration

    Energy of Photon/Red-shift, inflation, acceleration I have a few questions (following a short premise) below. I have been reading medieval philospohy recently and also some about the "Big Bang." What I am struck by is number of assumptions made in both fields. There is a large amount of...
  11. S

    Question about Sonic Doppler Shift Speed Measurement

    BACKGROND: Myself and a number of others are doing a thing called Dynamic Soaring with our special purpose built radio controlled gliders. We are getting them going very fast; in the range of 300-320mph. We have verified a top speed of 309mph using radar guns but that is the highest that...
  12. J

    Red shift and zero point energy

    Is there a relationship between red shift of galxies and zero point energy? Has the zero point energy changed over time?
  13. B

    UV Star Redshift 8: Doppler Effect Impact on IR Spectrum?

    Hello friends! Would a star (O-Type) with max output peaking in the UV range, which was subject to (at distance) redshift 8 end up in the IR spectrum when its light approached earth? Would this be taking into consideration the doppler effect? BTW, yes this is somewhat an extension of my...
  14. Saladsamurai

    Questopn about phase shift SHM

    Question about phase shift SHM The displacement of an object is given by x(t)=x_mcos(\omega t+\phi) If the inital displacement is 0 and the initial v is in the negative x direction, then the phase constant must be ___rads I know that if x=o then the cosine of the phase must be 0...
  15. M

    Apply Phase Shifts Using FFT for Gaussian Noise Signal

    What I want to do is apply a frequency-independent phase shift to a Gaussian Noise signal. Obviously I can just invert it to get a pi shift. Also I can take the Hilbert transform to get a pi/2 shift and I can invert that to give myself in effect a 3/2pi shift. BUT... what I want to do is to be...
  16. wolram

    Measuring Red Shift with Accuracy

    We have measures that define the volt, amp, kilo, pressure, etc, etc, compared to these measures how accurate are red shift figures? i know that tolerances are only guaranteed in a machine shop if the temperature is within limits, and all the above can be tested time and time again, but how...
  17. Bob3141592

    Gravity Red Shift: Can it Happen?

    Can gravity be red-shifted? I've never seen this addressed directly, but I don't see how it couldn't be. If gravity isn't affected by the expansion of the universe, why isn't it? If it is red shifted, would this dimunition of gravity be like a repulsive force?
  18. T

    Doppler Shift: Same Direction, Same Velocity?

    a Concept Question. Is there a Doppler Shift if the source and observer move in the same direction with the same velocity? Explain . Can someone drop their comments and ideas ..? please and thanks you.
  19. dontdisturbmycircles

    "Adjusting to Night Shift Work: My First 8.5 Hour Shift Starts in 2 Hours

    I just accepted a job offer for a position stocking shelves in a grocery store... at night. I originally asked for a shipper/receiver position but eh, I wanted the job anyways. Anyways, I had my interview at 1pm and I start today for my first 8.5 hour shift at 11pm, in 2 hours. Ahh I am...
  20. J

    Phase shift using a series capacitor

    I have a single phase mains supply which I need to split it into two phases, then shift one of them by 90 degrees relative to the other (with peak values of both waveforms having the same magnitude). I know this is generally done by two branches in parallel, with a series capacitor in one...
  21. P

    Binary Jacobi Symbol Algorithm: Add, Subtract & Shift

    Jacobi Symbol - Binary NOTE: if its past 8:30 AM Eastern Time, don't worry about it. thanks for the consideration The Question: Exercise 13.1. Develop a “binary” Jacobi symbol algorithm, that is, one that uses only addition, subtractions, and “shift” operations, analogous to the binary...
  22. I

    Why -3db frequency shows 45degree phase shift?

    help me guys... i reall need the answer ASAP...:cry: Thanx in advance..
  23. A

    Question on Relativistic Doppler Shift

    I have a quick relativity question. Say an observer is moving at a relativistic velocity with respect to some light source that emits light at one particular frequency (the observer's path does not intersect the emitter). At the point of closest approach, will light from the emitter be Doppler...
  24. B

    Doppler shift formula and the assumptions behind it

    Einstein in his "On the electrodynamics of moving bodies" (1905) starts the derivation of the Doppler shift formula by stating: In the system K, very far from the origin of coordinates let there be a sourcce of electromagnetic waves..." . Taking into account his advise "never stop thinking" we...
  25. M

    Solving 90 Degree Phase Shift Problem with Acclerometer Signal

    Hi. I get a signal from an acclereometer that I integrate using an op-amp to get the velocity. But the problem is that this signal is phase shiftet 90 degree. Because I'm supposed to compare this signal with a reference signal that is 180 degree phase shiftet, and now I'm getting wrong...
  26. S

    Identifying a Perihelion Shift Solution

    Hello, this is my first post. I am a programmer from Regina, SK Canada who likes to learn about Physics when I have spare time. My question: Does anyone know the name of the following solution for the perihelion shift? I do not know who to attribute it to. Thank you for your time. For...
  27. M

    Calculating Phase Shift for a Series RC Circuit

    Homework Statement A resistor of 362 Ohms is connected in series with a capacitor of 50.0 µF capacitance. A sinusoidal signal of f = 11.7 Hz experiences an impedance of 452.836 Ohms. Find the phase shift between the current and voltage at f = 11.7 Hz. Homework Equations I tried using...
  28. S

    Doppler Shift in Binary stars?

    I know that in spectroscopic Binaries, you can observe wavelength shifts in each star. But how do you determine the total radial velocity of this system alltogether, and how do you find each star's radial velocity?
  29. K

    Is there a maximum doppler shift?

    I was playing around with a thought experiment where an observer is moving towards a light source at a speed infinitesimally less than C and it seems like, for any given wavelength, the maximum possible Doppler shift is 1/2. for example near infrared light with a wavelength of 800 nm would be...
  30. M

    Cosmological Red Shift: How Does z Change With Time?

    I know that the variation of cosmological red shift with the distance is given by z= H_0 l (1+\frac{1}{2} (1+q_0) H_0 l) Where l is the luminosity distance, H_0 is the Hubble parameter at the corrent epoch and q_0 is the deceleration parameter. I would like to know how does z...
  31. T

    Sun's Polar Shift on 2012 coincidence?

    Ok, these are the general facts... - NASA states that the sun has gone through a polar shift on the year 2001 and will go through another one on 2012. http://www.gvnr.com/74/3.htm - For people who don't know, the Mayans had the most precise calendar of their time. The calendar states...
  32. 6

    Simple filter circuit: Phase shift

    Hello all, I'm currently taking an upper division circuits class as a MechE student after taking a 2 year break from the topic. We were given a problem to find the transfer fuctinon T(s) of a high and low pass filter, and then plot Vout(t)'s phase and magnitude vs. the freq. My question...
  33. J

    How Do You Calculate the Frequency for a 90 Degree Phase Shift in Coils?

    Hello All, I did an experiment recently involving two coils in series with a high frequency signal running through them. My goal was to determine at what frequency the signal in one coil would be phase shifted by 90 degrees with respect to the first coil. I was able to experimentally...
  34. Q

    Is the Doppler shift an independent principle?

    Is the Doppler shift an independent principle of wave mechanics? Or we can deduce it from other principles of wave mechanics? The article [1] gives an analogy of throwing and receiving balls. But it may be inappropriate. We are discussing wave mechanics? Why bother an analogy of balls/particles...
  35. kach22i

    Weight Shift at speed (acceleration and braking)

    Let's say you have a body in motion, a car, an airplane or hovercraft - does not matter, looking for basic laws of physics here. 1. You know the weight. 2. You know the center of gravity at rest. 3. You know the center of lift (if applicable). Let's say our object weighs in at 600...
  36. S

    New form for GR's gravitational red shift & a novel interpretationof the underlying physics

    [Moderator's note: the message is posted because it had to be an enormous work to write it. LM] I am posting an unusual version of the standard relation for the gravitational red shift embodied in general relativity. This new version uses the Klein-Gordon equation, sans psi notation, and gives...
  37. F

    Astronomy and the Relativistic Doppler Shift

    Homework Statement The hydrogen atoms in a star are also moving at high velocity because of the random motions caused by their high temperature. As a result, each atom is Doppler shifted a little bit differently, leading to a finite width of each spectral line, such as the 656.46-nm line we...
  38. K

    Phase shift from path difference

    1. Homework Statement A wave front moving horizontally encounters a block of glass that has an index of refraction of 1.50 in its upper half and an index of refraction of 1.25 in its lower half. The wavelength of the wave front in air is 700 nm. At what lengths would the glass block cause...
  39. Q

    USA Military paper about Psi phenomenon Paradigm Shift?

    USA Military paper about “Psi phenomenon”... Paradigm Shift? Hi everybody, The USA Military has recently (year 2004) approved for public release and distribution a very interesting and controversial research document titled “Teleportation Physics Study.” In this document they talk about...
  40. P

    What is the Period of the Sun's Rotation Based on Doppler Shift of Light?

    I have to calculate the suns period time, when given the following information; "The H_{alpha} line has the wavelength \lambda_0 = 656.1~nm . Measuring this spectrum from opposite sites of the suns equator, shows that there is a difference between that is \Delta \lambda=9\times 10^{-12}~m ...
  41. S

    Does Motion Affect Frequency in Sound Waves?

    Hello, The reason for the shifting of freqeuncies of all types of waves in response to relative motion away or towards the center of propagation, is caused by a corresponding stretching or compressing of the medium, correct? I mean for sound, if one moves toward the place where the sound...
  42. M

    Deriving Doppler Shift Using Spacetime Diagram

    Alright, I'm trying to derive the dopper shift using a spacetime diagram (see attached). If we model light pulses then we can derive the distance between the pulses in time, and hence the doppler shift... right? So, if we make some light pulses along some sort of time event in the x, cT frame...
  43. T

    What is the parallel shift of the light beam?

    a parallel glass plate with a thickness of 30 mm and a refractive index n = 1.65. A light beam hits the surface under an angle of β = 45°. (a) What is the parallel shift of the light beam? what is the meaning of parallel shift?? pls help
  44. E

    Should I Shift by 1 or 4? Understanding Fourier Transform Time Shift

    I am given this signal: x(t) = sin(4(t-1)) and I need to find X(jw), i.e. it's FT, so I am confused whether I shift by 1 or by 4, in other words whether I multiply F{sin(4t)} by e^(4jw) or by e^(1jw) which one is it? I am thinking it's 4jw... is it right?
  45. Q

    Exploring the Doppler Effect: Red Shift, Blue Shift, or Just Curiosity?

    This might be a stupid question, but it came to me the other day while reading. Since the speed of light is the same in all frames what would happen if you were chasing a light beam at .999% c, so you were heading right for it (but could never catch it) and it is ahead of you traveling at c. If...
  46. C

    Fourier Transform and Shifting in Solving ODEs?

    Find the solution (in integral form) of the equation: u(x+1,t) - 2u(x,t) + u(x-1,t) = u_t u(x,0) = f(x) Hint: Use the shift formula F[f(ax-b)] = \frac{\exp{i\omega b/a}}{|a|} \overline{f}(\omega/a) So I took the Fourier transform of each term using the shift formula: \exp{(-i\omega)}...
  47. L

    What is the derivation for ΔN in the MM Experiment: Fringe Shift?

    I am reading Paul Tipler's Fundamentals of Modern Physics, (Worth Pub., 1973) and would like to understand how ΔN (Eq. 1-5, pg. 6) )is arrived at. Here is the derivation as I understand it up to that point: Michelson devised an experiment to determine the difference in the number of fringes...
  48. A

    Redshift and Velocity: Deriving Expression & Determining Velocity Direction

    A 14.4 KeV photon from 57 Fe is red shifted as it rises from a sourceat ground level to an absorber placed at the top of a tower of a height of 20 m because it has to expend energy to climb the gravitational potential. Derive an expression for thered shift as a fraction of the energy of the...
  49. S

    Red Shift - From Dark Material Or Recession?

    Hi! I'm new here and I have a question I hope you can help me with. I'm curious about the conclusion that our Universe is expanding and ask if the evidence of Red Shift is reliable enough - or, could the apparent Red Shift be caused by interference from Dark Energy/Matter distorting our...
  50. S

    Nuclear Volume Shift: Isotope vs Vol. Shift Explained

    In two successive questions I am asked to calculate the first order perturbation shift corresponding to 1) isotope shift for the 1s-2p transition for deuterium and hydrogen 2)nuclear volume shift for deuterium I get a larger answer for the isotope shift than the volume shift, and then I am...
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