Waves are disturbances that propagate through space and time. Classically, they travelled through a medium, disturbing the particles but not changing their mean position. Electromagnetic waves/particle-waves need no medium; they are disturbances in their respective fields.

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What would the effects of the GW150914 gravity wave burst be on observers much closer that 1.3B LY? [duplicate]

The effects of the GW150914 gravity wave burst were barely observable with state of the art instruments, i.e. LIGO. What would the effects of GW150914 gravity wave burst be on observers much closer ...
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How Can LIGO or Any Such Gravitational Wave Detector Detect Displacement Which Are Billionth of Times Smaller Than Mirror Tolerances

I am very excited about GW150914, the maiden direct detection of gravitational waves. Since i am naive about experimental nitty-gritties, allow me to pose a naive question: After all the interference ...
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64 views

Wave equation in classical mechanics!

We represent the wavefunction of any wave on the string as $$y=f(x-vt),$$ where $v$ is velocity of the wave and $x$ is distance from origin and $t$ is time taken to reach the given point and $y$ ...
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35 views

Optics of stationary waves

could anybody tell me how it Works if it comes to stationary waves created on the surface of water jet and optics? there are some crests and troughs which work like lenses, but if you have water jet, ...
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51 views

Wave intensity and superposition

Let us say we have 2 point sources of sound. My question is how do we consider the intensity to vary according to position? Let's say both have same amplitude, frequency and speed, just different ...
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28 views

Wave generated with particle excitement

To my understanding, an electromagnetic wave(infact two perpendicular fields) will be emitted when a particle(e-) shifts from higher energy orbital to lower energy orbital but what would be the ...
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37 views

Wave speed question wave equation given in terms of exp [closed]

Question A wave propagating along the x axis . The displacement of the particles is along the Z axis at t=0 is given by Z= exp[-(x+2)^2] where x is in metres . At t=1 Z= [-(2-x)^2] find the speed ...
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Is it possible for a harmonic to be louder than the fundamental frequency?

Using most sound equations, it is quite clear that increasing frequency decreases amplitude, but is there any example where this is not true?
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352 views

What was Newton's own explanation of Newton's rings?

What was Newton's own explanation of Newton's rings? Newton advocated a corpuscular theory of light, but his rings would most conveniently be explained by a wave theory. How did he explain his own ...
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40 views

Why would a decreased length mean a higher frequency of sound?

This is in terms of the Water Bottle Lab: adding water (effectively decreasing length) to a bottle and finding its fundamental frequency at different lengths/amounts of water. I understand what ...
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4answers
51 views

About speed of sound?

Even though Speed of sound at room temperature is very large equal to 342m/s yet it does not cover that much large distance when we speak. What are the conditions at which sound really travel 342m in ...
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3answers
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Baryonic acoustic oscillations: Why are there standing waves in the CMB?

On page three of the following http://www.quantumfieldtheory.info/CMB.pdf, Klauber talks about the formation of standing waves from acoustic vibrations in the early universe. He claims that they form ...
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39 views

3D Standing wave [closed]

I need to derive an equation (like a vibrating string) of a 3D vibrating object having a mass ‘m’(object itself made of bunch of closely packed particles, in-between the particles there should be an ...
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25 views

Given Tension and the wave equation, how do you find the linear density?

I am given that the equation of a transverse wave of a string is y(x,t) = 2.00mm(sin(25.1rad/m)x-(415 rad/s)t) and the string is under 18 N of tension. From the tension, I got that the string is ...
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44 views

Why can a wave only have a single frequency if it goes on to infinity?

I have read that the only way a wave can have a single frequency is when it goes on for all infinity. Could someone explain me in plain english the reason?
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Why are sound waves adiabatic?

I want to know why we can treat sound waves as an adiabatic process. Precisely, I know that pressure and density vibrations occur so fast that molecules have no time to exchange energy (I might be ...
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How can you make harmonics on a string? [duplicate]

For an oscillating string that is clamped at both ends (I am thinking of a guitar string specifically) there will be a standing wave with specific nodes and anti-nodes at defined $x$ positions. I ...
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3answers
61 views

Normal mode analysis

I'm reading lots of texts about normal modes and I've seen that normal modes are solutions of the wave function produced by separation of variables. However, when most of authors I've read perform the ...
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2answers
64 views

Why Counter waves are being produced in water?

While studying water waves in a cuboidal tank, the following observation was made. A gentle tap on one side (A)of the tank, generated waves from that side towards the opposite (B). At the same ...
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1answer
29 views

Why is sound intensity defined as the product of pressure and particle velocity?

The intensity of a sound wave is defined to be $$\vec{I}=p(x,t)\vec{v}(x,t)$$ I can see that the units on either side of the equation balance, but I can't find a derivation online that shows why ...
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15 views

Physics 3 recommended book with solutions [duplicate]

I'm new to this forum and wanted to ask for a recommendation for a book which has these subjects with problems and solutions:(if this is not a valid question please tell me) -Intro to Waves -Fourier ...
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61 views

Matter wave's properties

The matter waves are not electromagnetic waves, so, can they be coloured like the visible region of the electromagnetic wave spectrum? Any examples as such?
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27 views

Standing Waves in a String of two Linear Densities

Given a string with sections of two linear densities like this: Does the point where the two linear densities meet have to be a node if a standing wave is produced? Are there alternatives? Could I ...
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59 views

Do photons traverse through the vacuum of outer space as a helix? [duplicate]

I’m trying to understand “Electromagnetic waves”. If electromagnetic waves traverse as a helix then do photons traverse as a helix?
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Why is it said that standing waves do not transfer energy?

The author of my physics textbook writes that standing waves, unlike travelling waves, do not transfer energy. He says that this is because a standing wave is composed of two travelling waves carrying ...
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54 views

Why do pulses get reflected by a fixed end?

Consider the case where a pulse hits a fixed end. I want to know the physics behind the following two phenomena 1) Why does the pulse get reflected? 2) Why does the pulse get inverted? I somewhat ...
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Amplitude-Modulated Wave in a Dispersive Medium

Amplitude-Modulated Wave in a Dispersive Medium. An amplitude-modulated wave with complex wavefunction $a(t)=[1+m\cos(2\pi f_st)\exp(j2\pi\nu_0t)$ at $z=0$, where $f_s\ll\nu_0$, travels a distance ...
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23 views

Help understanding the wave number in light

For my final optics project I want to implement the beam propagation method using Fourier transforms. I came across the following document ...
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50 views

Classical wave equation - validity

I know that classical wave equation carries for spherical wave fronts. In addition, Huygens' principle states that any wave front is a superposition of many spherical wavelets, so why does the ...
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1answer
19 views

When EM waves travel through a material with refraction index n, is the formula $\lambda = \frac{c}{n \cdot f}$ correct?

When EM waves travel through a material with refraction index n, ist the formula $\lambda = \frac{c}{n \cdot f}$ correct? c is the speed of light in vacuum and f the frequency of the wave. Thank you!
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36 views

Does frequency of a vibration wave of a cantilever depend on its deflection?

cantilever= a beam fixed at one end only deflection is the initial displacement of the free end. the beam is let go when the free end reached its position it will vibrate, does the frequency of ...
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23 views

Standing waves arbitary frequency

Suppose I have a string that is fixed rigidly at one end. Now when I start making wave, it will get reflected and should lead to standing waves (Mathematically and by visualization), but then we have ...
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27 views

1D transmission lines wave equation solution

you may know that the solution of 1D wave equation by d’Alembert is F(x-ct)+F(x+ct) and my question is that like is this F(x-ct) at transmission lines only the equation of one forward going wave that ...
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42 views

What is the significance of a function being a solution to the wave equation?

I understand how the wave function is derived. I also understand how to check if a function serves as a solution to the wave equation: If a function is solution to this wave equation, what does ...
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89 views

Standing wave on a circle [closed]

Suppose that we have a standing wave on a circle. I heard that by gradually increasing the radius of the circle, the wavelength will also increase to keep the standing wave. Is it right? If yes, ...
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45 views

How fitting is the sound wave (transverse wave) propagation model? (for the layman)

Air is a gas, then how is sound wave propagation possible? I mean, gas particles have a tendency to travel in a straight line, so how does a sound wave occur via compression and rarefaction? Most ...
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36 views

Is it possible to generate deep infrasound with subwoofer and a pipe?

I would like to check if infrasound noise can make people feel weird (as in a "haunted" house). Some people claim that noises of such frequency may be the cause of "paranormal" sensation in humans. ...
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90 views

Is double slit interference due to EM/de Broglie waves? And how does this relate to quantum mechanical waves?

I'm really confused about the fact that there seems to be two types of waves at play: the EM wave, which I understand to be an actual fluctuation of EM fields in space, and this other type of bulk ...
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41 views

Distinguishing transverse and longitudinal from wave equation

Can we distinguish if a general wave or disturbance $f$ (not necessarily electromagnetic) which satisfies the wave equation \begin{equation} \frac{1}{v^2}\frac{\partial^2 f}{\partial t^2} = ...
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1answer
76 views

Complex resonant frequency not resonant without imaginary part. So can I still just take real part as solution?

I am working with a matrix on a harmonic oscillator problem and the lowest (absolute) frequency $\omega_0$ where the matrix becomes singular is the resonant frequency. Now I obtained this frequency ...
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45 views

LinAc standing wave

I have a question regarding Linear Accelerators (Linacs): Originally, traveling HF waves were used to accelerate electrons inside a Linac. You can see a sketch in the following picture. The further ...
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Frequency of wave related with the speed of wave

Today I am studying about waves. So, we learn the formula "speed = frequency * wavelength". There is a question come out in my book If the frequency of water waves is decreased, what will happened ...
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how does reflection takes place in an open organ pipe [duplicate]

I'm interested to know how is there reflection without any boundary in an open organ pipe. It could be understood in closed one .
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39 views

What is difference between standing and non standing waves?

While reading about waves it was written in my book that standing waves have varying amplitude but constant angular frequency or time period. But I am not able to exactly differentiate between ...
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1answer
55 views

Finding mass attached to the string

I'm given the following problem: One end of a string with a linear mass density of 7.60* 10^-4 is connected to an oscillator with a frequency of 50.0 Hz. The other end is connected to a hanging ...
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1answer
32 views

Front velocity and Superluminal group velocity

In some cases, according to Wikipedia, the envelope of a gaussian beam can go faster than speed of light hence leading to superluminal group velocity. However, the signal/energy still propagates at ...
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2answers
57 views

Can every single sound ever made(from the beginning of time) be recreated again?

Sound is a wave and energy decreases as $1/r^2$ . The intensity of sound is proportional to $(amplitude)^2$ of the wave. So if we amplify the wave with some instrument then we can hear every single ...
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Regarding wave displacement equation [duplicate]

in some textbook i read that one can describe wave displacement by y(t)=Asin(ωt+ϕ) and y(t)=Acos(ωt+ϕ) . i know both these terms are periodic but how one can use any of these equations in numericals ...
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24 views

The initial conditions for the harmonic travelling waves

I'm given the following problem: For a harmonic travelling wave travelling in the positive direction, the initial transverse speed is 3 m/s and the initial $y$ displacement or transverse ...
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Relevant Archemidan Spiral Theorems: An Enquiry

Basically what I'm doing is investigating the solar wind's outflow. As part of this investigation is included a fairly crude application of a more complex outflow solution to that of basic archemidian ...