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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Relation between variation of tension and frequency of a standing wave

What is the relation between a variation of tension and the variation of frequency of standing wave in a rope? I get this expression differentiatin the relation between $f$ and $T$ $$f=\frac{1}{2L ...
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40 views

Light, the carrier of information. Is this hypothesis a known phenomenon?

I am seeking clarification on a naive insight that I experienced recently. It seems plausible and may be known to most academics and practitioners in the field but I would appreciate your knowledge ...
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36 views

Photon transmission

I want to know exactly how light travels. Are each photon in a light beam traveling in a cosine function? I'm confused because only when it goes through polarization that it starts to show this type ...
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0answers
24 views

Gravitational waves' Amplitude

Gravitational waves are disturbances in gravitational field which in turn is the curvature of space-time. So my question is it possible to somehow measure the amplitude of a gravitational wave and if ...
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1answer
58 views

Wave speed of a hanging rope

Let us consider a homogeneous rope hanging from the ceiling. I will call the vertical direction $x$ and the horizontal displacement $y$. When we apply the second Newton's Law to a portion of mass ...
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28 views

Mechanical energy in an harmonic wave and in normal modes

I think I miss something about energy of a mechanical wave. In absence of dissipation the mechanical energy transported by an harmonic wave is constant. $$E=\frac{1}{2} A^2 \omega^2 m$$ But, while ...
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29 views

Measured organ pipe eigenfrequency does not match the theory

There are many well-known homework assignments to find eigenfrequencies of an open organ pipe leading to the solution for the fundamental frequency of such a pipe: $$f_0 = \frac{c_0}{\lambda_0} = ...
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1answer
29 views

Problem with linear mass density of which varies according to the law $μ = kx + a$

I have some problem solving this exercise: A wire of length $L = 10$ m has a linear mass density of which varies according to the law $$μ = kx + a$$ with $k = 1.8$ g m-2, $a = 0.5$ g m-1. The wire is ...
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2answers
25 views

Finding Amplitudes of Resultant Mechanical Waves

Let's say I have two arbitrary mechanical waves $y_1$ and $y_2$ propagating on a string in the same direction. The waves $y_1$ and $y_2$ differ in phase by an arbitrary angle $\phi$ and the ...
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3answers
33 views

Explanation as to why the sum of two sinusoidal waves, differing by only phase, can be represented by $2y_{m}\cos(\frac{1}{2} \Phi)$

How does the addition of two waves, differing only by phase, collapse to $2y_{m}\cos(\frac{1}{2} \Phi)$? Wouldn't the $\omega$ component of the wave still come into play given that it determines the ...
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10 views

Acoustic energy

Let's Assume that I'm sitting in a hypothetical container(room) whose 6 walls are PERFECTLY AND IDEALLY rigid and also are PERFECTLY reflective. Now if I start speaking anything in this room and so ...
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511 views

Are EM radiation and EM waves the same thing?

Are EM radiation and EM waves the same thing? I have seen this topics treated separately in many books. It is still not clear to me whether EM radiation and EM waves are synonymous. Is there any ...
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26 views

Is it possible to have two waves of different frequency on one string?

Would this change for different Hz, Wavelengths, Speeds, or amplitudes?
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19 views

Why do smaller wavelengths image particles more clearly when the particle size is already big?

Yesterday I scanned an ultrasound phantom that had cylindrical inclusions (1.5mm diameter). When I boosted the ultrasound frequency from 3MHz to 4MHz, these inclusions became much more clear. I ...
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2answers
79 views

Which wave carries more energy? [closed]

Which wave carries more energy? This is a school question (in a course a friend is taking) but I am interested in the answer:
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21 views

Huyegns Principle and data transmission

Huygens's principle (The Gist) states that for every object on which light is incident every point on that object acts a light source till light is being incident on it. So is it possible than WiFi ...
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2answers
47 views

How to derive wave speed/tension relation for the vibrating string?

I was studying vibrating strings and in my teacher's notes I found that, generically, if I change the tension on the string by $\Delta T$ then, the speed percentage change can be written as: ...
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1answer
69 views

Diffraction wavelength relationship [closed]

This question appears somewhat similar to other questions asking about why wavelength affects diffraction (a concept which I'm still not 100% sure on...) however my query is different and not answered ...
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1answer
21 views

Medium particle velocity vs wave velocity

It is said that wave may have a uniform velocity. We could think of the time when exactly the 1/3 th wavepulse has finished pasing through this point, and 2/3th numbered wave pulse would do this ...
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3answers
32 views

Phases and sinusoidal waves

When we're talking about a wave, just a singular sinusoidal wave, what exactly is a 'phase'? I came across a question that gave values of frequency ($550$Hz), and speed ($330$m/s). The question then ...
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1answer
26 views

Which information do we get from the phase spectrum about the wave?

Let a wave is represented by an equation $$y=f(t)=10\sin(\frac{2\pi f_1t}{T} + \pi/6)+5\cos(\frac{2\pi f_2t}{T} +\pi/3)$$. Here, let us take $f_1=10 ,f_2=5 ,T=100$ Then, from the Fourier transform ...
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1answer
32 views

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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1answer
40 views

Can gravitational waves interfere polarize or show any other properties of stndard waves

Is it possible for gravitational waves to be able to produce phenomenon such as interference and polarization etc. which are observed in standard waves. Also is it possible for gravitational waves to ...
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4answers
676 views

Which formula for the de Broglie wavelength of an electron is correct?

So, I have my exams in physics in a week, and upon reviewing I was confused by the explanation of de Broglie wavelength of electrons in my book. Firstly, they stated that the equation was: $\lambda = ...
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9 views

Explain quality factor and bandwidth [duplicate]

Can anyone explain concept of quality factor and bandwidth with a mechanical example?
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0answers
40 views

Why does thicker aluminum do better at reflecting wifi

I have performed a experiment based one the ability of aluminium reflecting wifi radio waves. I have found out that the more aluminium foil i put on my reflector, the better result I can get. I did up ...
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When light reflects from a medium of lower index of reflection to a medium of higher index of refraction, why does the light undergo a phase shift? [duplicate]

I learned in my physics class that there is a phase shift when light reflects off a low $n$ from a higher $n$, but never got the explanation.
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27 views

How does cavity resonance produce EM waves? [closed]

My understanding is it acts like a capacitor and inductor in a loop. The capacitor releases stored energy which is absorbed by the inductor through a magnetic field which then returns it to the ...
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1answer
95 views

Is meters per second equivalent to seconds per meter?

I know this question is probably ridiculous, but bear with me for a moment. This thought emerged while I was converting between nm and wave numbers ($\rm cm^{-1}$). In order to prove this conversion, ...
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0answers
20 views

Solving traveling wave using the shooting method

The spatially-dependent Hodgkin-Huxley equation for a cylindrical dendrite or unmyelinated axon: where $\frac{a}{2\rho}\frac{\partial^2V}{\partial x^2}$ is a diffusion term $a$ is the fiber radius, ...
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55 views

Plucking Guitar Strings [closed]

I was given this prompt: A musician frets a guitar string of length 1.5 m at x = 0.28 m with one finger, and simultaneously plucks the string at x = 0.14 m with another finger (raising it to a height ...
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2answers
23 views

Simple harmonic waves

When a simple harmonic progressive wave is travelling through medium,then each succeeding particle lags in phase before the preceding particle.Can anyone expain how does it lag? Thanks…
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1answer
21 views

Is it possible to low pass filter the amplitude of a sound wave?

Is it physically possible to block or attenuate noise above a certain amplitude, but leave other lower amplitude noises unhindered?
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1answer
23 views

Can you have a problem with a Dirichlet boundary condition but with waves that reflect off the boundary?

Say we are looking for a solution to the Helmholtz equation $$(\Delta + k^2) u = 0,$$ in in the upper half space ($y > 0$) in 2D with a Dirichlet boundary condition on the $x$-axis, that is, $u(x, ...
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124 views

Transverse Wave [closed]

Tranverse Wave is travelling in a string.
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2answers
171 views

Rope waves with a twist

In the picture you see a person walking a slackline. A slackline is a tensioned flatband of polyester. Typical tensions are between 1 kN to 15 kN depending on the length of the line. The lines are ...
3
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3answers
84 views

Why is the Plane progressive wave equation $y= a\sin (kx-wt)$ for positive direction of x-axis?

Likewise, why is $y= a\sin(kx+\omega t)$ for negative direction? What is the basis/derivation for this?
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2answers
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What is the player's role in the functioning of a theremin?

I recently see a video on how the theremin works, and wasn't satisfied with the answer. I watched around, but they all seem to give the same explanation. A diagram as below is given, and it is ...
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1answer
34 views

Wave Velocity vs. Phase Velocity

I am trying to understand the difference between 'wave velocity' and 'phase velocity'. I know that generally they are equal, but when is that not the case? I, of course, tried to google it, and ...
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1answer
46 views

How do waves transfer mass?

A similar question was asked here, however the discussion was led astray by involving the equation $E=mc^2$. I know that waves transfer energy, but do they transfer mass? And, if they do, what would ...
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11 views

Energy density of a transverse

I'm finding it hard to understand the concept of energy density of a transverse wave. I know the formula, but I can't quite get my head around it. I know energy density is energy over volume, but ...
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3answers
732 views

Don't all waves transport mass?

How do matter waves not transport mass? I know that matter waves are associated with moving sub-atomic particles(which is insignificant for macroscopic particles). If a wave is associated with a ...
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3answers
29 views

Is the speed of a wave determined by the medium in which it travels, the frequency of the source, or both?

I know that for a string of linear density $\mu$ and tension $T$, the wave speed is given by $v=\sqrt{\frac{T}{\mu }}$. Additionally, the speed of any sinusoidal wave is given by $v=\lambda f$. My ...
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3answers
78 views

An experiment to show sound waves

My 6 year-old son asked me to explain the sound barrier. I think I'm ready to explain, but I wanted to know if I could add a little homemade experiment to show visually how soundwaves are generated. ...
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1answer
40 views

Derivation of the wave equation from Hooke's law- Generalization question

Following the derivation on the relevant Wikipedia page, I am having a bit of trouble moving from the following line, with the case of 3 particles in a row: $$ \frac{\partial^{2}}{\partial t^{2}} ...
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2answers
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Do mechanical waves also carry momentum as well as energy? [closed]

I have read that electromagnetic waves carry momentum because they carry energy, while energy is equivalent to mass. So they carry momentum. But this explanation is in the context of special ...
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1answer
18 views

When should I use the phase constant in the equations of waves?

In the equations of Waves, I find that somewhere they have used the phase constant and somewhere haven't. While deriving the formula of standing wave they assumed two equation as $ y_1\; =\; y_0\, ...
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4answers
57 views

Is the speed of sound in air constant?

In Optics lecture we took a formula for the speed of a wave which is: $$ v=\frac{\omega}{k} $$ where $\omega$ is number of complete vibrations per second: $$ \omega=\frac{2\pi}{\tau} $$ and: $$ ...
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1answer
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Conservation of energy in a sound wave

I have two ultrasonic transducers, an emitter and a receiver, and I'd like to know how the energy of the spherical wave is conserved. I guess the energy is proportional to its amplitude and it ...
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Problem in understanding the interpretation of $-T_0\frac{\partial\psi(z,t)}{\partial t}\,.$

I've been reading in Frank S Crawford's Waves, travelling waves and reflection. Here in the following quotes, the author interprets the term $\frac{\partial \psi(z,t)}{\partial z}$: The power ...