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. L

    Relativistic Doppler Shift for Transverse Movement

    Homework Statement A sodium light source moves in a horizontal circle at a constant speed of 0.100c while emitting light at the proper wavelength of λ0=589 nm. Wavelength l is measured for that light by a detector fixed at the center of the circle. What is the wavelength shift λ-λ0? Homework...
  2. Helmholtzerton

    A Z-coordinate shift when using elliptical integrals?

    Hello, I'm wondering if my approach to a problem is correct as when I try to simulate the DC magnetic field of a current loop using elliptical integrals, I obtain results that appear incorrect when shifting the current loop's location from the origin of the z axis. I have attached the...
  3. C

    I Shift of momenta cures IR divergence?

    Consider the following integral $$\int \frac{d^4k}{k^2}$$ It is UV divergent but is it IR finite or IR divergent? The integrand is singular as ##k \rightarrow 0## so this suggest an IR divergence but this is no longer the case if I make a shift of the loop momenta by say ##p_1## and write the...
  4. P

    A Does an increase in gain cause peaks to shift right?

    In a spectrum from an MCA (that is hooked up to a scintillator and PMT), does an increase in amplifier gain cause the peak to shift towards higher channels? I have a source and its really weak so while calibrating my detector, I had to turn the gain up way high to see a peak, but I'd preferably...
  5. Q

    Phase shift measurement using phase modulated signal

    Hello everyone, I'm actually working on developping a phase shift sensor using one phase modulated signal, i know that the title is confusing beaucause the phase shift measurement need two signals , I'm trying to do this with the zero crossing method so if I could found the timestamps of the...
  6. P

    Voltage and current phase shifting/Current without voltage?

    Hello, I've recently been learning about capacitance and inductance causing the current to lead or lag. But how can the current possibly maintain the same waveform? Shouldn't the zeros of voltage and current always align? How can there be current without voltage?
  7. BL4CKB0X97

    B Is blue shift as common as red shift?

    A somewhat trivial question, but I hear of redshift a lot more than blue. And is possible to get a list of galaxies that display these attributes? I would like to use the data for a project. Thanks guys.
  8. T

    I Red shift and the maths for gravity

    I have looked but do not seem to be able to pin down how Hubble's Constant deals with Gravity. Is it considered as Newtonian or Einstein special theory?
  9. mpolo

    How to calculate the Doppler Shift Frequency

    I would like to know the formula for calculating the Doppler shifted frequency received by someone on Earth that is received from a spaceship traveling at 85 percent the speed of light away from Earth. Please show example of the formula being used. Let's say the spacecraft sent a radio signal...
  10. A

    SN1 Rxn: is hyrdride shift major product or the LG position?

    Homework Statement So LG is on 2° position, and you have a hydride shift. So you form one product on 2° and one product on 3°. Which product will be major which will be minor? Homework Equations none. The Attempt at a Solution I know hydride shift will be more major than a methide shift...
  11. J

    I How can I identify the appropriate spectral line for Doppler calculation?

    Hi, I was looking into Doppler shift calculations, and I came across this blog post. It gives a very simple and straight forward account of calculating the velocity of a star. Following is the summary the blog post: Spectrum of Alpha Centauri (A. Cen.) is obtained through Lhires III...
  12. Vital

    Graphs of sin and cos, how to set points for x values

    Homework Statement Hello! I am at the topic on graphing trigonometric functions. Exercises are rather easy at this point, but I have a problem deciphering how authors of the book choose points for x values. Please, take a look at few examples (including screen shots I attach), and, please...
  13. U

    Doppler shift source velocity components

    how does the doppler effect work when the observer and source are not moving in a straight line, what do we take in as the velocity of the observer and the source in the doppler effect equation?
  14. U

    Doppler shift source velocity components

    Homework Statement Why does a source moving perpendicular to the line between it and the observer produce no doppler effect?Homework Equations The Attempt at a Solution I have heard the the radial velocity of the source relative to the observer must be zero but i don't understand why, if the...
  15. C

    Phase shift of e.m. wave through a glass plate

    Homework Statement Consider a glass plate of refraction index n and thickness ## \Delta x ## placed between a point monochromatic source S and an observer O, as in picture. (a) Prove that, if absorption from the plate is neglegible, then the effect on the wave received by O is the add of a...
  16. ReidMerrill

    Interpreting NiCl2 (dppe) H-NMR Peaks: Chemical Shift Analysis

    Homework Statement I'm trying to interpret an H-NMR of NiCl2 (dppe) and am trying to match the peaks in the aromatic region. Homework Equations 3. The Attempt at a Solution [PLAIN]http://[URL=http://s350.photobucket.com/user/remerril/media/hnmr_zpseljx6e8x.png.html] I think that the...
  17. S

    I Photon number state and Doppler shift

    If a mode of light is in the single photon state in the reference frame of the emitter, what will the state look like in a reference frame where the wavelength is, say, 5% less or more? How about a state with, say, 5 photons? I saw some online discussions and some papers on arXiv (not...
  18. Const@ntine

    Phase Shift of two sinusoidal waves

    Homework Statement Two sinusoidal waves in a string are defined by the wave functions y1 = 2.00 sin (20.0x – 32.0t) y2 = 2.00 sin (25.0x – 40.0t) where x, y1, and y2 are in centimeters and t is in seconds. (a) What is the phase differencebetween these two waves at the point x = 5.00 cm at t...
  19. C

    I Relativistic doppler shift and radar

    Consider at stationnary radar at the origin ##z=0## and a target (speed ##v##) moving along the ##z## axis and away from the radar. The radar is sending plane waves (frequency ##f_i##) to the target and they come back to the radar (the radar is then both an emitter and a receiver). I am...
  20. A

    I Lamb shift and the QFT vacuum....

    I think I already know the answer to this, but I'm looking for a source: Can the Lamb shift be explained entirely in terms of radiative corrections due to the self-interaction of the hydrogen's electron with its own EM field? That is, is it necessary to reference vacuum polarization or related...
  21. AishaGirl

    Can Light Wavelength Remain Unchanged at High Velocities?

    Homework Statement A probe is launched with velocity v=0.8c. A beacon emits a light with wavelength \lambda=500nm in its rest frame. Years later the probe is located by NASA using a telescope, When they measure the light they find the wavelength \lambda=500nm in their rest frame. Is this...
  22. Andy_K

    I Doppler Shift and Light Quanta: Questions on the Nature of Light and Observation

    Dear All, I have a couple of (noob) questions regarding Doppler Shift and light from a quantum physics perspective: a) Since different observers will see the light at different frequencies depending on their reference frame / velocity thus resulting in Doppler Shift, does that mean that any...
  23. R

    Doppler shift derivation from Lorentz Transformations

    Homework Statement Show how one can obtain the Doppler transformation for the frequency of a receding source just using the Lorentz transformations for the energy (where E=h). Homework Equations Relativistic transformations for momentum and energy: E = γ(E' + vp'x) pc/E = v/c = β The Attempt...
  24. D

    Find effective value and phase shift for the current I

    Hi guys! I am wondering if someone can help me with an assigment i got, i would appreciate if someone could help me with it. Find effective value and phase shift for the current I in the link the tip is to use the superposition theorem http://imagizer.imageshack.us/a/img924/3673/R5qIAN.png
  25. Meerio

    I By what formula is this graph predicted? Cumulative Periastron Time Shift

    I'm confused about how the predictions of this graph were formed. I have this formula: But the change in frequency per second is about : 2x 10^-12 which has a problem because when you multiply this by 10 years you don't even get a change of frequency of 1/1000 of a second and in the graph it...
  26. U

    Understanding phase shift w/ time of 2 different frequencies

    Hi all, I hope this question is of an acceptable format to ask about here. I'm just having trouble trying to get a conceptual understanding of the following. I've been told that if I'm given two different frequencies that are completely in phase at time equal to zero, then I can find their...
  27. Kara386

    Energy shift in excited state sodium

    Homework Statement The spin-orbit interaction in sodium results in fine structure with energy shifts given by: ##\Delta E_j = \frac{C}{2}[j(j+1)-l(l+1)-s(s+1)]## If ##l##, ##s## and ##j## describe the single outer electron in sodium. Show that if this electron is excited to a state where l>0...
  28. just wandering

    I Why don't any stars "look" red? red shift

    Universe is expanding/galaxies moving away from each other and far away galaxies are moving away from us faster. so the light is redshifted. .."at very large redshifts, much of the ultraviolet and visible light from distant sources is shifted into the infrared part of the spectrum. This means...
  29. teetar

    Determining phase shift of two frequencies

    Homework Statement I'm given two frequencies: 4,000 Hz, and 5,000 Hz. They are completely in-shift at time ##t=0##. I am to find the time it takes them to get completely out of phase. Homework Equations The Attempt at a Solution I've not gotten waves very well thus far in physics. My teacher...
  30. T

    Phase Shift Oscillator

    1. The problem FIGURE 4(a) shows the circuit of an oscillator and FIGURE 4(b) gives the gain and phase response of the op-amp used. When the circuit was simulated in PSpice using an ideal op-amp, the circuit oscillated at the designed frequency. However when the ideal opamp was replaced by the...
  31. G

    A Why does Finite Size Scaling shift the Phase Transition Down?

    See the title. I'm not sure that this is the right place to post this question, but I'm not sure it fits any better on any of the other boards. Let's say you have a phase transition. The correlation length will scale as: ξ = |TC-T|ν This diverges on both sizes of the phase transition. Now...
  32. kostoglotov

    Will an infinite impedance cause no phase shift?

    Homework Statement imgur link: http://i.imgur.com/0Zc8nQe.png Homework Equations Y-Delta transformations The Attempt at a Solution Since it's a proof, I can't check the answer in the back. What I did: I transformed the three impedances in their delta config to a Y config, and my TI89...
  33. Hongo

    I Radio Comm Between 2 Points Diff Gravity: True?

    A source that is orbiting close to a singularity of a black hole is transmitting a radio frequency signal that lasts 60 seconds and is repeated infinitely. The signal is being transmitted using the amplitude modulation method (AM Radio). Let suppose that each minute passing in the transmitting...
  34. S

    Doppler shift and change in intensity of a sound wave

    How are the intensity of a sound wave and the Doppler shift of frequency related togheter? That is, if the source or the observer are in relative motion, how does the intensity change? For a sound wave $$I=\frac{1}{2} \rho \omega^2 A^2 c=2 \pi^2 \rho f^2 A^2c$$ (##c## is sound speed, ##\rho##...
  35. wolram

    B On the relativity of red shift

    arXiv:1605.08634 (cross-list from physics.pop-ph) [pdf] On The Relativity of Redshifts: Does Space Really "Expand"? Geraint F. Lewis Comments: 6 pages, 5 figures, appeared in Australian Physics Journal-ref: Australian Physics (2016), 53(3), 95-100 Subjects: Popular Physics (physics.pop-ph)...
  36. D

    Car's weight shift with torque & angular momentum

    I am having trouble visualizing which two tires of a car will be pushed down based on the angular momentum and torque of that car. Let's say if its angular momentum is point OUT while its torque is pointing UP in relations to the picture below. My guess is it's the two right wheels of the...
  37. F

    Help with Doppler shift galaxy question

    Homework Statement Hi, I'd really appreciate being pointed in the right direction with this past exam question, as I just have no idea how to approach it and can't find similar examples in my notes anywhere. A nearby star has a spectrum similar to the sun, suggesting it has the same mass. The...
  38. K

    Zero phase shift Op-Amp bandpass filter design

    Homework Statement "design a band pass circuit having a midband gain of 20 dB with -3 dB frequencies at 20 Hz and 20 KHz the amplifier should not produce any phase shift." does midband gain strictly apply to voltage gain (because that's how i look at it)? I was going to use a common collector...
  39. gsmtiger18

    Phase shift of light incident on 2 slits

    Homework Statement Light of wavelength λ = 450 nm is incident upon two thin slits that are separated by a distance d = 25 μm. The light hits a screen L = 2.5 m from the screen. It is observed that at a point y = 2.8 mm from the central maximum the intensity of the light is I = 55 W/m2. a)...
  40. J

    Value of a wave at a time with a phase shift.

    Homework Statement Calculate the value of the wave at t = (2, 3, 4, 10) ns 0.4 cos(10^8 * t + (1/3) * y) az Homework Equations N/A The Attempt at a Solution This is the last part of a problem. I have already found the phase shift of 1/3 and wavelength of 6 pi. I have already been given the...
  41. F

    I How can I calculate red shift for intragalactic bodies

    Hello everyone. I am doing an studi on Be stars, all of which are inside the Milky Way, I want to show that the red shift won't be a big deal here, but I am confused about how to prove it; what I have done is combining the equations λr=λe(1+z) and cz=Hd to get λr=λe(1+Hd/c) where z=v/c. I get...
  42. BiGyElLoWhAt

    I Doppler shift for an observer in circular motion

    Say we have an observer in perfectly circular motion around a source, like a star. Is it reasonable to apply the angle change formula ##cos \theta_o = \frac{cos \theta_s - \frac{v}{c}}{1-\frac{v}{c}cos \theta_s}## and then take the component of the motion parallel to the light wave in the...
  43. K

    Can I Create a 15 Degree Phase Shift with Transformers?

    I was wondering how I can get a 15 degree phase shift with transformers. I know a delta wye transformer creates a 30 degree phase shift.
  44. H

    Inertial tensor remains diagonal during a shift along a principle axis

    In the middle of the below paragraph: "only if the shift vector ##R## is along one of the principal axes relative to the center of mass will the difference tensor be diagonal in that system." I suppose the difference tensor means new inertial tensor ##-## old inertial tensor. That means the new...
  45. L

    Courses Shift from biotechnology bs to astrophysics masters

    Hi, i am currently studying in biotech university. As I'm going up to 3rd year, i need to choose a major (i study in europe). The only choices i have are molecular biology and environmental technology. However, i have always been wanting to study and pursue career in astrophysics. Due to...
  46. P

    I Not understanding Hulse Taylor period shift calculation

    I have been studying Hulse Taylor PSR 1913+16 calculation of period shift which is regarded as indirect proof for gravitational waves, but I don't understand one thing. If you look on the graph of Cumulative period shift, around every 10 years the shift doubles...
  47. Jorrie

    Perihelion Shift in Near-Circular Orbits: 6πm/a + Higher Order Terms

    The full power series for the Schwarzschild portion of perihelion shift is given in Mathpages as: where L = a(1-\epsilon^2), a the semi-minor axis and \epsilon the eccentricity. This implies that as \epsilon tends to zero, the perihelion shift tends to a non-vanishing 6\pi m/a + some much...
  48. brainbaby

    Phase shift issue in Dominant Pole Compensation strategy....

    Hello guys please help me on this... The next hurdle in my understanding of frequency compensation comes as following… As the text says… My problem is that as we move from point 1 to 2, the frequency increases so the phase shift should also increase..(as phase shift depends on frequency)…...
  49. S

    Engineering Phase shift oscillator and circuit

    Homework Statement Gain & phase response of TL072 op-amp Homework Equations 'Frequency of oscillation was observed to be about 15 % lower'[/B] Why ? The Attempt at a Solution so at this frequency the op-amp has 45 phase shift, but why will this impact the oscillator and lower the...
  50. G

    Second Shift Theorem Homework: Why f(t-1) ≠ 0?

    Homework Statement why the f(t-1) isn't = 1-1 = 0 ? since f(t) = 1 , a=1 Homework EquationsThe Attempt at a Solution
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