Doppler Definition and 713 Threads

Suppose a person is traveling towards a wall with a tuning fork at frequency 'f' at a speed of 'v*'. Using the doppler effect equation: f' \ = \frac{v + v_o}{v - v_s} What would the sign of v_o and v_s be? I don't understand, since the man is both the observer and the source. (Let - be...

I have a problem here. I stole me a grad student and he didn't really know what to do either. Without further adoo (or whatever), i give you... the problem! There are 3 trucks transmitting on the same frequency. #2 is stationary. #1 moves to the left at velocity v. #3 moves up at velocity v...

I'm working on the following problem: Two submarines are underwater and approaching each other head-on. Sub A has a speed of 4 m/s and sub B has a speed of 18 m/s. Sub A sends out a 1010 Hz sonar wave that travels at a speed of 1522 m/s. The question asks two questions, but I'm stuck on...

Doppler Radar?? Please can someone help me with doppler radar...need to know bandwidth?? Is it usually continuous wave or pulse?? or can it be both?? pretty much just after some general knowledge on doppler radar? thanks in advance!

What is the difference in magnitude between the effects of normal doppler effect and doppler effect in accelerated frames, e.g. when the (light)source is accelerating wrt the observer? What is the formula for doppler effect in accelerating frames?

Hi. I am doing a project about the Doppler Effect and I was wondering if someone here could help me. I have a tone source and I need to find the frequency with respect to time. I could use my mp3 player to record this frequency, which will then save it as a .wav file. I was wondering if...

Hi all. I was reading: http://www.astro.ucla.edu/~wright/doppler.htm but I'm failing to understand this part: My understanding is that a galaxy cannot move faster than c (the speed of light). Why then could a galaxy moving close to c have a recession velocity greater than the speed of light...

Question: The variable period of a moon of Jupiter, which is the basis of measurement of the speed of light in Roemer's method (whoever he is), is regarded as the Doppler affect. The period of the orbital motion of one of Jupiter's moons is approximately 42.5 hours; the speed of light is...

I need to find what the distance between Earth and saturn would be if they were both in a straight line with the sun (both on the same side of the sun). The problem I'm trying to solve involves the doppler effect, and I can work it out if I know that distance. Does anyone know what it is...

I'm having trouble solving this one: Two motorcycles are traveling in opposite directions at the same speed, when one of the cyclists blasts her horn, which has a frequency of 544 Hz. The other cyclist hears the frequency as 563 Hz. If the speed of sound in air is 344 m/s, what is the speed...

Hey, I need a bit of help with the derivation of Doppler's equations as shown in the attached image. (From Fundamentals of Physics) The paragraph where it states "Now let us again consider the situation..." I don't understand why they use vt + vDt I mean, the sound wave would initially have...

I've got 2 qns 1) Student holding a tuning fork vibrating at 440Hz walk away from a wall with a speed of 1.2m/s. What's the freq of the echo the student can hear from the wall? Speed of sound is 330m/s Can i just use Freq= [(330-1.2)/(330+1.2)] (440Hz) to solve 2) A car traveling at 10m/s...

Question: Imagine a space probe has been placed in a circular orbit about a distant planet. The probe emits a continuous radio signal with a wavelength of 8 m. You measure the signal from earth, and find it to have a wavelength that varies regularly between 7.99943 m and 8.00057 m, with a...

How can we apply the doppler effect when the source of sound is coming towards us at supersonic speeds?Is there a mathematical method for it?

Why is it that the extent of the doppler effect on sound depends on whether, for example, you are moving towards the source or the source is moving towards you? Why does this not happen for light?

I have been working on this problem for over a half hour. I'm not sure where I'm going wrong with it. If anyone could help me out I would really appreciate it. You stand by the railroad tracks as a train passes by. You hear a 1000 Hz frequency when the train approaches, which changes to...

In "Concepts of modern physics 6/e by arthur beiser", there's a paragraph on pg11 explaining th effec on the observer moving perpendicular to a line between him and the light source. Why is the proper time between ticks to=1/vo?

If you are driving in a car up to a set of trafic lights that are red, how fast would you need to be going to make the lights appear green? (take the velocity of light to be 3x10^8 ms-1 and the wavelength of red light to be 620nm and the wavelength of green light to be 540nm) Ive calculated...

Suppose a sound source S is moving towards a stationary wall and that a listener L1 is moving with the sound source. Describe in a few lines why the reflected sound heard by the listener L1 is Doppler-shifted by about twice the amount that a second listener L2 would hear standing by the wall...

Hi, I am sort of a new to physics. So far I've only been doing motion, up to the formula for average power. However I was reading something in Earth Science as I was going to help someone study for their regents test, you know how school is almost over and all. Then I read about the Doppler...

Hello, There's a problem with the doppler efect that I don't understand. When a object runs at a velocity a little minor than velocity of sound, appears in front of the emisor a group of high frecuence, that in simulators (applets) is increasing in time. This wave, is like a physical...

I don't know how to understand doppler shifts and yet conserve energy. Consider a red photon is emitted by a torch. This photon is let free to travel through space. Any observer at rest relative to the torch (which by now may be millions of miles away) will see it as a red photon...

hey just wondering about the doppler effect and how it is used in meterology, law enforcment and astronomy. I know for law enforcment they use it in radar guns, and astronomy i think for finding the distance of planets? Any other ways it used? and also how is ultra sound used in medicine...

generic redshift is characterised (defined) by z = (L-L0)/L0 where L is the wavelength at time of absorption (detection), and L0 was the wavelength at time of emission. for Doppler redshift z = v/c for small (non-relativistic) values of v. assuming the universe is expanding, I've read...

A block with a speaker bolted to it is connected to a spring having spring constant k = 21.0 N/m, as in Figure P17.40. The total mass of the block and speaker is 46.00 kg, and the amplitude of this unit's motion is 0.475 m. Assume that the speed of sound is 343 m/s. Figure P17.40...

Hello. I have a question on Doppler effect. When the wave has the same velocity that the emisor, u have this: f= \frac {\partial {(Vs-Vo)}} {\partial {(Vs-Ve)}} f' In this case, Vs=Ve, f=infinite?

I am to measure the rotational velocity of Io relative to Jupiter, and will do so using a spectrograph. I will measure the frequency change of a specific mineral emmision band in the spectra, and then check how much it has shifted from its original wavelenght with a table. Then I use the...

uestion is How does the second order term in teh relativistic doppler shift (v/c)^2 compare to the total classical Doppler Shift for the observer receeding away from the source? now the doppler shift (relativistic) is \Delta f = |f_{0} (1-\sqrt{\frac{1-\beta}{1+\beta}})| for the...

A lithium atom with initial velocity of 1000m/s (x hat direction) will be deflected into a positron cloud by a laser of wavelength 670nm. The laser beam is 1mm high and 15cm long and has an average power of 1mW. As the atoms absorbs each pohoton it is deflected in the yhat direction by a small...

In class we were explained that if the source moves toward the stationary observer f' = f_{0} \frac{v}{v-v_{s}} where f0 is then aturla frequency of the wave, v is hte speed of the wave, and vs is the speed of the source and f' = f_{0} \frac{v_{rel}+v}{v} where vrel is the speed of...

I know which equations to use for solving Doppler Effect problems, so figuring out which is the observer and which is the source and which is moving or stationary is not the problem, the problem I am having is in solving the actual formulas... This question might belong in the math help section...

In the doppler effect equation for sound, measuring frequency, I have the following question: Car 1-20m/s--> Car 2-30m/s--> --POINT A-- With the above "diagram", we have car 1 going at 20 m/s, right, and car two, 30m/s right, with respect to point A (doesn't have to be those values...

I was reading somewhere that the because of the red shift it can be concluded that the galaxies are moving away from us. But still when we talk about stars, red color refers to cooler stars rather than stars moving away from us. Why?

do you get a doppler shift when your moving towards a light source? like, i know light gets redshifted with expanding space and gravity, but if light always approaches you at the same speed, how would frequency change there?

Doppler effect revisited Am I right when I say that the doppler effect formula "f=f0((v+vo)/(v+vs))" is derivated from the classical theorem of speed addition and this is why the doppler effect for light and EM waves is different?

If a source and detector are moving towards one another, for the general doppler equation, would this be considered the source moving or the detector moving?

I know that the typical values of Doppler coefficient over core life are about -1 *10^-5 Deltak/k/°F at BOL and -1.5 * 10^-5 Deltak/k/°F at EOL. What are the value in SI units? Are they the same, but in Kelvin? Thanks, Ken

when observing heavenly objects, there is an important role of doppler effect. but is there a way to distinguish whether the red/blue shift is because of translational, rotational motion or perhaps thermal motion of the atoms?

There is a space shuttle service between Earth and mars. Each spaceship is equipped with two identical lgihts one at the frotn and one at the rear. The spaceships travel at constnat speed u0 relative to Earth such that an observer standing on Earth sees the headlights of an approachin ship as...

For the relativistic doppler shift: change in wavelength = (c - Vs) To / (1 - Vs ^2 /c^2)^1/2 where Vs is emitter velocity, c is speed of light and To is time. Suppose change in wavelength was equal to just 1 / (1 - Vs ^2 / c^2)^1/2 then (c - Vs) To = 1 c -Vs = 1 / To c = Vs + 1...

Hi everyone, really would love it if someone could help me with this. I think it's probably a very easy problem, only I can't seem to find the right formlula, or understand the only one I found... This is the problem: I'm in my car, driving towards a crossing with a red traffic light...

Assuming the speed of light is constant from all reference points I don't quite understand why the Doppler Effect works for electromagnetic waves. From my understanding, as far as sound is concerned the object "catches up" with the sound wave, increasing the wave's frequency. But how can that...

A while back I was involved in a discussion regarding the difference between the classic Doppler Effect equation and the Relativistic Doppler Effect equation explaining red/blue shift in stars. I went looking for how to derrive both formulas and came across this interesting article that...

I saw in a chapter on special relativity a derivation of the transverse Doppler effect, which seemed okay, but I have a question concerning this: If the motion of a source is always perpendicular to the position vector connecting the observer to the moving source (i.e. the distance remains...

As I understand it, light will be redshifted when it travels from a large ( gravitationally speaking ) object to us. It will also be redshifted if the object is moving away from us. How do we know how much of the redshift is due to either effect ? :confused:

A train moving toward a detector at 31m/s blows a 305-Hz horn. What frequency is detected by a statiory train? Using the equation f´= f(V + Vd/ V - Vs) The answer is supposed to be 340-Hz but I don't understand how to get it. Mind helping me out?

What is "FOR"? doppler shift? What is "FOR"? I believe it an acronym having to do with the doppler shift? :confused:

Photon Doppler Shift? I am a practicing EE who has used the standard Doppler shift equation for thirty years in radar design; therefore, I am not disputing the correctness of the equation but the "explanation" that is so often given in textbooks. The general explanation always discusses...

The Doppler effect corresponds to a percieved change in the wavelength of impinging light, correct? Does this mean that the Absorption spectra we would see for bodies in relative motion to light sources should be the same independent of the type of motion between the body/source (assuming that...