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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149 views

Linear polarized 3D glasses and the physical shape of light waves

Looking into how linear polarized 3D glasses work, I keep getting explanations that boil down to this: However, I always assumed that a light wave was depicted in diagrams like this... ...to more ...
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2answers
57 views

Intuition behind Airy waves dispersion relation

Using Airy wave theory, one can derive the dispersion relation of water waves (under some physical assumptions): $$ \omega^2 = gk\tanh{kh} $$ where $k$ is the wave number, $h$ the distance from the ...
4
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1answer
68 views

Why is TV remote's infrared wave shown by a camera as purple light, why not red or something else?

I've always seen that all the old model remotes that is used in DVD players or TVs, it emits electromagnetic waves, having wavelenth somewhere in the Infrared region. But when my phone's average ...
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0answers
45 views

WHY do waves diffract - what is the mechanism behind the diffraction?

Having recently studied wave diffraction at an introductory level, I don't feel that I understand why waves diffract like they do. What is it about the obstacle or the waves interaction with it which ...
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1answer
96 views

Can sound reflect from itself?

If it is possible, what kind of conditions would be necessary? The case with electromagnetic waves could also be interesting, but I don't think that is possible.
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2answers
134 views

How do transverse sound waves (in solids) convert to longitudinal waves (in gases)?

I know that in solids sound can be a transverse wave and that in gases it is a longitudinal wave. The question is what happens at the boundry at the two substances? What is the mechanism of conversion ...
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2answers
115 views

How is energy conserved in resonance?

According to Wikipedia, [...] resonance is a phenomenon that occurs when a vibrating system or external force drives another system to oscillate with greater amplitude at a specific preferential ...
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1answer
33 views

Physics of waves under an ice road

As wikipedia writes, While easier to drive across in the winter than land, roads over water present a great danger to anyone using them. Speeds are typically limited to 25 km/h (16 mph) to ...
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0answers
25 views

Wave pulse on the string

When we consider a pulse on a string,a vibration is produced by snapping one end of the rope in which one end is fixed at the wall.Then what happens to air molecules which is just above the pulse?Is ...
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1answer
30 views

What is sound intensity?

In my medical physics book it says that Intensity is 1/2 a2/pc=a2/2z Where a is the amplitude, p medium of density, c velocity of that wave and offcourse Z is the impedance. When I google it it just ...
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3answers
144 views

Could sound be considered a kind of renewable energy? [closed]

Is sound energy useful as a source for generating electricity? If so, could it be a renewable resource?
3
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1answer
48 views

Does a trumpet play at a tritone lower without lip vibration?

My trumpet teacher noticed that if you blow into a trumpet for warm-up, without any lip vibration, there is still a slightly audible pitch which is a tritone lower than "expected" in the following ...
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1answer
96 views

Total number of primary maxima in diffraction grating

I am trying to determine the total number of primary maxima that can be observed when light of wavelength 500 nm is incident normally on a diffraction grating, with the third-order maximum of the ...
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0answers
27 views

Why isn't the de Brogile equation not λ=2(h/p) [duplicate]

So I was thinking about the two equations: $E = \frac{1}{2}mv^2$ And $E = hf$ Then $\frac{1}{2} * mv^2 = hf$ $\frac{1}{2} * pv = hf$ $\frac{\frac{1}{2} * pv}{h}$$ = f$ $\frac{pv}{2h}$$ = f$ ...
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1answer
41 views

How far away must I stand to not hear sound (interference) [closed]

I`ve been trying for a while. I have two speakers with 4 meters between them with music playing on 250 Hz so the wavelength is 1.36 meters, How far away do i have to stand in front of one of the ...
0
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1answer
88 views

Clarification about two forms of the wave function

The wave function in the position representation is $\langle\ x\rvert\psi\rangle$ = $ \psi (x) $ , where $ \psi (x) $ are the continuous coefficients that multiply the orthonormal basis vectors, i.e, ...
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1answer
32 views

Effectiveness of Layered EM wave shields [closed]

Which is best at shielding EM waves; a Faraday cage with sides made of blocks of metal, or layers of metal (with insulation ie plastic & without), or is there no difference between the three? ...
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1answer
46 views

Calculating angle of refraction of water in this lab setup? [closed]

The setup of the experiment is as drawn in the picture (where the red circle is a rotating disk, the box is a laser and the straight line the laser beam and the semi circle in the middle of the ...
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1answer
63 views

Waves and Sound [closed]

An organ pipe of length 1.5 m is open at one end. What are the lowest two harmonic frequencies? As it is open, $V = 2lf$ $V = 343m/s$ Therefore: $343 = 2 \cdot 1.5 \cdot f$ $f = 114.33Hz$ But ...
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0answers
54 views

Single Slit/Double Slit path differences

When diffracting light through a double slit, I understand that the two sources must arrive on the screen m(wavelengths) out of phase [where m is any whole number], in order for a bright fringe to ...
2
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1answer
112 views

How to find the first-harmonic frequency from the frequency spectrum of a recording of this harmonic being struck on a guitar?

Just as the title implies, I was trying to find the fundamental frequency of a guitar string at various tensions as a part of an experiment to find its Young's modulus. In the experiment, I connected ...
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1answer
27 views

Resulting amplitude due to two equidistant sound sources

If sound sources have same amplitude say $A$ and nearly same angular frequency like say $\omega_1$ and $\omega_2$ then at a point equidistant from them is it correct to assume that the ...
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2answers
34 views

Why is the sound channel in the ocean especially good for low frequency sound?

Why does not the high frequency sound propagate as far? The dispersion curve $\omega(k)$ is almost linear, right?
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0answers
25 views

A question about the sound channel in the ocean

The sound channel (SOFAR channel) in the ocean is about 1000 meters below the surface. It is said that sound can get trapped in this channel and propagates thousand kilometers without dissipation, ...
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1answer
51 views

Electromagnetic Shielding of radio waves

Would a radio wave beam (perhaps a cm in diameter) with the same frequency as ordinary AM or FM radio waves and also the same voltage (v/m) have the same skin depth for any metal utilised to shield ...
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1answer
67 views

dynamics&forces of hydrofoil wave surfing

I'm puzzled by apparent ability of hydrofoil to surf [ocean's] wave, as evidenced by this footage. Let's compare it to ordinary surfboard. Let's focus on "static" condition when the board is position ...
3
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2answers
87 views

Is Huygens-Fresnel principle applicable for waves other than light?

In Wikipedia it was mentioned Luminous disturbance so I Did get confused that this principle only works for light waves and not for all of the Waves. Like some mechanical waves example wave on string. ...
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1answer
31 views

Monochromatic light and interference [duplicate]

What I want to ask is monochromatic light necessary for interference? Doesn't interference occur on just the superposition of two waves(any waves)? And Why don't waves of different wavelengths don't ...
2
votes
1answer
55 views

What the term 'phase' in a wave actually means? [closed]

I actually want to clear my conception about the phase. I have used it while dealing with wave equations. But could not get the actual significance of it. I have learned that, 'phase is a quantity by ...
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2answers
65 views

Can we determine the location of a radio station if we know the wavelength and frequency of radio wave emitted by that radio station?

let say that we can detect the wavelength and frequency of radio wave then can we detect that from where these radio waves are coming or from how much distance these waves are coming?
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0answers
69 views

Intuitions for the simplest model in which the evolution of the laws of nature arises from the natural selection of structures [closed]

The problem I’m trying to solve can be described as To create the simplest model possible in which the evolution of the laws of nature arises from the natural selection of structures. This approach ...
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1answer
26 views

The sound energy when two or more objects collide

When two objects collide in an inelastic collision, some kinetic energy is converted to sound energy and heat. How do I determine how much of the kinetic energy is converted to sound energy? Provided ...
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3answers
252 views

How are gravitational waves exactly produced?

I was thinking about gravitational waves, and I found out that I may have a doubt about their production. Assuming the whole calculations find a wave-like solution to be understood, I was wondering ...
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1answer
42 views

Tension in a vibrating loop

Consider a super basic 1D vibrating string, with standing waves on it. The string has length $L$, and the wave propagates at a velocity $v$. The fundamental frequency $f_1$ is given by $$f_1 = ...
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2answers
4k views

Why can't the human voice produce a Shepard tone?

Audio of a shepard tone on youtube. So what is a Shepard tone? A Shepard tone, named after Roger Shepard, is a sound consisting of a superposition of sine waves separated by octaves. When ...
0
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1answer
72 views

What is meant by 'Phase velocity is $c^2/v$' [closed]

Is phase velocity $c^2/v$ or $v/2$? Is there only one phase velocity as indicated by the above formula? If yes then why is wavepacket said to be superposition of 'waves' whose velocity is termed as ...
0
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2answers
35 views

Conceptual doubt regarding Standing Waves, in particular constructing a Standing Wave after t=T/2 seconds

Suppose you are given with the following figure: And you have to sketch the shape of the standing wave after T/4 seconds where T denotes the Time period. What will be the shape of the curve? As ...
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0answers
20 views

Do longitudinal waves travel more quickly in denser gases?

I understand that sound waves are longitudinal, and they travel faster in water than in air. However, would this imply that longitudinal waves travel more quickly in denser gases?
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0answers
18 views

Slowest mode of two string with different masses

I was watching MIT OCW recitation course. For most slowest mode, we have frequency with $\lambda= 4L$ when, the total lenght of string is $2L$. But for second slowest mode, why we do not take $\lambda ...
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1answer
43 views

EM Wave shielding of different frequencies

Is more aluminium required in Faraday cages to block AM or MW radio waves compared to FM frequencies (of equal power)? If yes, is this difference directly proportional to the decrease in frequency (FM ...
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4answers
37 views

What is the distinction between a “ray” and a “wave” in optics?

What is the distinction between a ray and a wave in optics? From what I can gather, the only discernible difference is in nomenclature, where a ray simply refers to an EM wave with short wavelengths. ...
3
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1answer
29 views

Traveling wave solutions for an irregular “waveguide”

I'm looking at solutions for the wave equation $$\frac{\partial^2 z}{\partial t^2}=c^2 \nabla^2z,$$ in a finite 2D domain. Say that I have periodic boundary conditions on the left and right edges ...
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2answers
36 views

A conceptual doubt regarding Longitudinal Waves

I was recently studying about Longitudinal Waves and I have a little trouble understanding the Displacement versus distance graph for these waves. Firstly, how exactly does one come up with such a ...
2
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1answer
65 views

Is there really no transverse sound wave in air? [duplicate]

Everything has some viscosity. The viscosity of the medium may support transverse wave, right? So, is there really no transverse sound wave in air?
3
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1answer
64 views

Conceptual doubts regarding the Graphs of Mechanical Waves

Suppose the above two graphs describe a wave, then I've a couple of conceptual questions that I don't fully understand. 1) Is there an analogy that I can use to imagine the graphs? For GRAPH 1 I ...
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1answer
42 views

How does the interaction between individual electrons of beams affects the diffraction pattern?

Consider the diffraction of an electron beam. How does the interaction between individual electrons of beams affects the diffraction pattern? If it really affects the diffraction pattern, then is ...
6
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1answer
81 views

Fractional harmonics in musical Instruments

I recently did some Fourier transforms on different audio files containing saxophone or trumpet (John Coltrane/Clifford Brown). I found that with the saxophone, the frequency spectrum occasionally ...
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1answer
57 views

how can interference occur within diffraction?

My book says : The number of interference fringes occuring in the broad diffraction peak depends on the ratio d/a that is the ratio of the distance between the two slits to the width of a slit. In ...
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1answer
22 views

Wave on a string to sound wave

If you have a string of 2m in length, and the wave speed on the string is 2m/s. and when then string vibrates at fundamental frequency the wavelength of the wave would then be 4m. However, the sound ...
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0answers
37 views

Is there sound diffraction grating? [closed]

Sound is also a wave phenomenon. Therefore, is there any counterpart of the usual optical grating for sound?