The Doppler effect refers to change in the observed frequency of a wave if the observer and source are in relative motion.

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Relativistic Doppler effect derivation

This is about a step in a derivation of the expression for the relativistic Doppler effect. Consider a source receding from an observer at a velocity $v$ along the line joining the two. Light is ...
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Why Doppler shift is applicable to spectral lines alone?

In astronomical spectroscopy, Doppler shift is an important parameter. But why is it applicable to spectral lines alone, and not to the continuous spectrum in the background? Shouldn't the motion of ...
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Why does the classical Doppler formula make a distinction between movement of the source and movement of the receiver?

I've tried rewriting the Doppler formula to include only the relative velocity between the source and the receiver of sound waves. However, when I compare the results with the results of the formula ...
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The reason for the fading of galaxies?

Galaxies that are greater than a distance of c/H metres from Earth have recessional velocities exceeding the speed of light and begin to fade. Thus, theoretical astronomers 3 trillion years the future ...
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A problem on Doppler's Effect [closed]

A source of sound emitting a frequency of 660 Hz is moving counter-clockwise in a circular path of radius 2 m with an angular velocity 15 rad/s. A recorder at a distance from the source is moving ...
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How to calculate doppler shift in mobile communication system?

I want to know how the following equation comes from. $$f_D=\frac{1}{2\pi} \frac{\Delta\phi}{\Delta t}=\frac{v}{\lambda}\cos\theta$$ The picture above is drawn by me in mspaint (sorry for bad ...
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Doppler effect of matter waves

We all know that the relativistic mass of a moving object in Special relativity increases for an observer who is measuring it for a moving object. We also know the the concept of particle-wave ...
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According to the doppler effect , if my source is faster than sound , will I hear the sound backwards? [duplicate]

In a hypothetical situation,say I have a sound box with a very large volume and let's say it is placed pretty far away from me. If it travels towards me at a speed higher than that of sound in the ...
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Is it better to call the doppler effect a change in wavelength or frequency?

Why is it preferable to say that the doppler effect causes a shift in frequency rather than a shift in wavelength? I often read on websites that they define the doppler effect as a change in ...
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Is the rate of light emissions actually the frequency of the light?

I am confusing with the concept of frequency in the context of Doppler effect studying SR. The Schutz says, if the source emits pulses more frequently, then the observer would see the lights not only ...
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How is the Photoelectric Effect affected by Blue-Shifting

I was thinking about the Photoelectric Effect and Blue-Shifting when I came up with a thought experiment that I couldn't think of an answer for. The thought experiment is as follows: A metal plate is ...
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Time domain representation of a waveform from an accelerating source (doppler effect)

Consider the scenario where a stationary observer observes a source moving in 3 dimensions, emitting a signal $s(t)$. I would assume only the distance between the source and the observer, $x(t)$, has ...
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Doppler Effect: What is formula for Rate of Change of Period observed by accelerating receiver?

(I have looked at other questions relating to Doppler Effect with acceleration but none seem to provide the formula in question.) Edit: I wish to avoid using the Einsteinian relativity model. So ...
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Calculate velocity based on Doppler shift

I have a bicycle with a truck horn on it. I want to figure out how fast the bike is based on the reference frame of a stationary object watching the bike. I can use software to determine the pitch ...
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Doppler shift of light from stars and galaxies [duplicate]

I was reading about how we can ascertain whether a cosmic object is receding from or approaching us by studying the doppler shift of its spectrum- I mean the redshift and blue-shift. But we have no ...
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1answer
155 views

Influence of acceleration in acoustic doppler's effect experiment

Recently I've done an acoustic doppler's effect experiment for physics lab assignment. The setup was two microphones in a straight line, movable object with sound source and a pc with the usual sound ...
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Could I see the cosmic microwave background if it were Doppler shifted enough?

If I traveled fast enough, my current understanding is that visible light would be blueshifted to the blue/UV range, but also that microwaves and longer wavelength waves would be blueshifted into the ...
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Can Doppler Shift be used to calculate speed of an observed object?

Thanks for looking. Just musing over an idea this afternoon: if I had a radio controlled plane, I could obviously calculate its airspeed based on pings and the known speed of sound if it was ...
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How'd you explain Red shift and Blue shift with respect to Doppler Effect

I understand Doppler effect in Sound and Water because there we can observe relative speeds. But in case of light, the speed is same in all references so is the change in relative wavelength due to ...
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42 views

Time-dependent time dilation for circular orbits around a Schwarzschild black hole?

Take two clocks, one in a circular orbit around a Schwarzschild black hole and another with a distant observer. The time dilation factor between the two clocks is said (at ...
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319 views

Doppler shift for a uniformly accelerating observer

This was given in textbook as an example. An observer on a spaceship with a four velocity $u$ is approaching from $x = +\infty$ a star at rest in the reference frame $S$ while undergoing constant ...
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160 views

Why would a sweeping LIDAR or RADAR beam not produce an artificial Doppler shift?

Assuming a bi-static Radar or LIDAR with a stationary transmitter and a stationary target and a stationary receiver, with a sweeping RADAR/LIDAR beam reflecting off a stationary target: Why would the ...
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392 views

Tired light red shift hypothesis

Have there been any recent attempts to falsify the tired light hypothesis alternative to the Doppler shift explanation for the red shift, or is it simply ignored like the pilot wave quantum mechanical ...
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Would cosmological redshift be present in the following situation?

I'm trying to understand if cosmological redshift is just a secondary form of doppler redshift, or something else entirely. Suppose the two galaxies in the picture are receding from each other, but ...
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How can the angle to a pulsar be determined by measuring its redshift?

Suppose we (a spacecraft, probe, or similar) know our location only to within a few billion km (a few Tm) in any direction in 3D space, and we want to determine our location to a higher degree of ...
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Doppler: how to derive formule “source moving” from formule “observer moving”

A question like this has already been asked, with a satisfying explication (the relative motion of the source and the observer with respect to the medium (air) is different), but without a derivation ...
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What are the limitations of velocity selective coherent population trapping?

I'm somewhat familiar with limitations of Doppler cooling, particularly with the one photon recoil limit, but what I was curious about was what is the next barrier to cooling approaching absolute ...
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Ultrasonic Transducer Spacing

Given a SCH 40 steel pipe of diameter D and length L, what is the proper spacing for ultrasonic transducers in a Doppler Shift setup assuming the transducers are angled at 45 degrees? The reason for ...
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Curious question about light and photons

If a photon wavelength (e.g., yellow) is isolated from the other wavelengths that the sun emits (once it gets to earth), can that particular particle/photon be distorted slightly into a wavelength ...
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Is absorption imaging in ultracold gases (BEC) a method destructive of the system?

As of title, I wonder whether this imaging method heats the gas up to the loss of quantum coherence. Let's consider a specific example, a gas of 87Rb (Rubidium) and its D2 line. I might be wrong in ...
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Is there a doppler effect on the images of stars around rotating black holes?

I'm an illustrator working on a project involving rotating black holes like those discussed in "Gravitational Lensing by Spinning Black Holes in Astrophysics, and in the Movie Interstellar" by James, ...
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Coulomb excitation of a heavy nucleus

In Coulomb excitation measurements involving a stationary target getting excited, why do the de-excitation $\gamma$-rays get Doppler shifted and Doppler broadened as well? How can these be corrected ...
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Redshift of distant galaxies: why not a doppler effect?

How can I explain to my 17 year old pupils that the observed redshift of distant galaxies cannot be interpreted as a doppler effect and inescapably leads to the conclusion that space itself is ...
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How to explain Doppler redshift of light?

For other waves like water or sound, it is easy to understand Doppler effect, because for those waves, the speed of wave in different inertia reference frames changes. But for light wave, the speed ...
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Does a spaceship travelling at near lightspeed see the universe aging slow or fast?

Now I know this probably is well trodden territory, but this question has bugged me for some time, and I couldn't find a similar question in the archives (although plenty about relativistic time ...
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'Doppler redshift' Vs 'Cosmological redshift'

It is not difficult to understand the differences between 'Doppler redshift' and 'Cosmological redshift' conceptually. But how do astronomers distinguish them when doing observations?
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When a photon escapes a black hole, why is it red shifted? [duplicate]

I think that is how astronomers hunt for these elusive objects using radio telescope and also gravitational lensing, I'm wondering how these photons lose their energy while encountering black hole or ...
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Crest in Light Doppler Effect

The way it is explained in wiki Doppler effect in sound happens because waves of particles with biggest density called crest hits our eardrums more often if object is moving towards us (increased ...
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Bouncing sound off a wall

Let's say I am moving at a velocity $v$ away from a wall, and emitting a sound toward a wall. Is it true that I hear the sound at the same frequency that I emit it?
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What does the ratio $\frac{x-ct}{x'-ct'}$ signify?

$(x,t)$ being coordinates of any event in an inertial frame $A$ and $(x',t')$ being the coordinates of the same event in another frame moving with uniform velocity $v$ along the same direction in ...
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Is the amplitude proportional to frequency in electromagnetic waves?

In Einstein's 1905 paper, under the section: § 7. Theory of Doppler’s Principle and of Aberration Einstein derived the relativistic Doppler effect: $$f'=f\dfrac{1-\cos\phi \cdot ...
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Hearing sound when going supersonic

Suppose we are travelling supersonic along a straight line. Further up along the line, there is a stereo, that's emitting sound at a frequency that changes in such a way that the Doppler shift caused ...
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How is the speed in Hubble's law determined, if not from the Doppler shift?

Hubble's law originally mentions the speed (i.e. proper motion) of a receding galaxy, as calculated via the Doppler effect from the observed redshift. However, the observed redshift is today explained ...
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What are the characteristics of light entering a disk spinning at near $c$?

If I were to spin a translucent disk so that the edge is spinning at .9c and shoot a laser beam at it perpendicular to the edge, what would happen to the light as it travels in one end of the disc and ...
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Doppler shift from a transversely moving plane mirror

Below is the diagram of the question I have on the Doppler shift of a light emitted from a stationary light source $S$ at an angle $\theta_1$ toward a transversely moving plane mirror $O$ having ...
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Is there a standard of rest in the universe? [duplicate]

If you measure the cosmic background radiation you will find that in any direction it is roughly the same. However, if you were to travel near the speed of light relative to the Earth in a particular ...
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How large or small can frequency in the EM spectrum get?

The largest frequency range is gamma rays, but does the EM spectrum 'stop' somewhere? Like is there a limit to how large a frequency can get? Or how small frequency can get? Is it one of those things ...
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Doppler-shift of AC-electricity

A tram is powered by overhead wire, the wire has alternating voltage of 1000 V RMS, the frequency of the alternating voltage is 50 Hz. The rails are the other wire. The tram is moving at speed 100 ...
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Doppler effect and light

Approaching the speed of sound in an aircraft is relatively difficult, because the closer you get to Mach 1, the denser the pressure is around you (sound accumulates causing vibrations). Is there a ...
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Is an infinite Doppler effect plausible?

When I was young (which I still am) I was amazed by the sound jet fighters make when they break the sound barrier - a sound similar to an explosion which caused my school to shake. Later I learned on ...