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 is the name for the whistling “musical” sounds that change stepwise in pitch when a hollow tube is spun like a lasso?

You have likely heard those sounds, science museums sometimes sell Flexible plastic tubes you can whirl like a lasso. The air rushing by the end of the tube causes these sounds, which are admitted in ...
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Can we compute the magnitude of the stress caused by sound waves on a wall?

As a follow up to this question, Could we really compute the magnitude of the stress caused by sound waves on a wall? If so, How do we do that?
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Help With Difficult Deductive Proof [closed]

Suppose we have a Gaussian beam with a complex envelope expressed by the following equation 1: $$\tag{1} A_G(x,y,z) = \frac{A_1}{q(z)} e^{-ik \frac{x^2 + y^2}{2q(z)}} $$ where $$ q(z) = z+iz_0 $$ ...
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After quantization of electron vibrations, do we need electrons anyway?

The title question is not ment in a general context, but one in which goes to the plasmon theory. In that case, how is are the statistics (boson vs. fermions) of plasmons determined? And is there an ...
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426 views

What is an electromagnetic pulse?

Is an electromagnetic pulse a plain electromagnetic wave with one peak?
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176 views

What do light wave oscillations look like? [duplicate]

High school physics student here, so please bear with me for a moment. I know that light waves oscillate, but I don't know how. In textbooks and diagrams they're portrayed as wavy lines traveling ...
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3answers
404 views

How do waves have momentum?

A question on a practice test I'm taking is as follows: By shaking one end of a stretched string, a single pulse is generated. The traveling pulse carries: A. mass B. energy C. momentum D. ...
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5answers
803 views

Why do the high frequency waves have the most number of modes?

While reading the Wikipedia page of Ultraviolet Catastrophe, I came across how Rayleigh and Jeans applied the equipartition theorem. They told that each mode must have same energy. Now as the number ...
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464 views

Through a lens, which light beam reaches the screen first?

Imagine three light beams are "sent" to a lens simultaneously, they start at the same position but move towards the lens at different angles. The first light beam passes the lens at its edge, the ...
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89 views

A question over the reality of $\sin x$

Harmonic functions are in widespread use in physical descriptions of natural real phenomena. I am just wondering therefore how we can define $\sin(x)$ to be part of a real physical quantity (with ...
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6k views

Prove EM Waves Are Transverse In Nature

Why we say that EM waves are transverse in nature? I have seen some proofs regarding my question but they all calculate flux through imaginary cube. Here is My REAL problem that I can't here imagine ...
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96 views

What is the difference in the uses of $\omega t$ and $kx$ in wave equation?

We know that in a wave equation $y = A \sin (\omega t + kx + \phi)$, $y$ = Displacement of particle on y-axis (assuming transverse wave) $A$ = Amplitude $\omega$ = Angular velocity $k$ = wave number ...
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Are reflection and transmission coefficents real or complex?

Is it common practice to give reflection and transmission coefficients as the ratio of the respective waves with respect to the incident wave when written in complex form or real form? I have seen ...
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How radio waves penetrate through buildings?

For example how radio signals of a base transceiver station (BTS) penetrate through buildings?
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448 views

Sonic boom and resonance

Can the damage caused by sonic booms be seen as an example of resonance? that is, when the driving frequency (be the sound wave) is equal to the natural frequency of the glass being damaged?
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118 views

Would passing horizontally polarized light through a varying width vertical slit allow you to measure the positional (x) amplitude of light? [duplicate]

I have found closely related questions on StackExchange, but (surprisingly) not this exact question. Seems some answers say individual photons do not have amplitude, only when traveling with other ...
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281 views

Are matter waves (de Broglie) classified as transverse or longitudinal? [duplicate]

We know that waves are of two types: transverse and longitudinal, and we have studied about de Broglie waves as well, so which one of them is it? Or we have other means to classify them?
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120 views

Singing for physicists: How to resonate by body cavities with my voice?

My body has various cavities, such as my throat, mouth, chest, and nose. This cavities have resonant frequencies. I also have a voice box, which creates sound. How do I create sounds at the resonant ...
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83 views

Importance of the $\exp (i \bar{k} \cdot \bar{r})$ part of the plane wave equation

I am having trouble grasping how the equation $\bar{E} \left( \bar{r}, t \right) = \bar{E}_{0} \exp \left[ i \left( \bar{k} \cdot \bar{r} - \omega t \right) \right]$ fully describes a plane wave. ...
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wave-particle duality

I have been trying to understand "wave-particle duality" and other cases related to it. I am currently a college level student. I have few question which I am not getting answers clearly. In double ...
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Direction of Propagation of Wave

I've always been a little uneasy with the notion of direction of wave propagation, for some reason. I guess it's always been defined 'intuitively' and I want to know the limits of the concept. To this ...
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354 views

Simple PDE as a theory of everything?

For the sake of simplicity, I’d like to believe that there is one master non-linear partial differential equation governing physics. In particular, consider a Klein-Gordon form: $$ \frac{\partial^2 ...
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47 views

Will radio waves bend to reach receiver?

I was wondering if receivers just catch the radio waves that pass through, or if they actually attract the waves like a magnet. In other words, will a radio wave moving in a straight line bend in ...
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104 views

Simple harmonic motion versus oscillations

I want to see whether certain oscillations in my daily life, such as the oscillation of violin strings when plucked, are simple harmonic motion or not. Can we identify whether an oscillation is simple ...
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108 views

Light always particle in vacuum because it has no medium

My physics teacher told me that light in a vacuum is always in the particle form. So what happens if you perform the double slit experiment in vacuum? Will the light spread like a wave or will it have ...
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215 views

How do gravitational waves work without internal tension?

One implication of general relativity is the concept of gravitational waves or gravitational radiation, ripples in spacetime thought to travel at speeds close to the speed of light. As far as I have ...
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211 views

Does “apparent frequency” mean the Doppler effect is not an actual physical effect?

When discussing the Doppler effect, we use the word "apparent frequency". Does that mean that the frequency of sound is still that of the source and that it is some physiological phenomenon in the ...
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198 views

Why Light isn't like an Acoustic wave?

I just wanted to know why light isn't an Acoustic wave.Is it because light wave doesn't obey acoustic properties?
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774 views

What is the mathematical equation for a sine wave? [closed]

(Guitar player and programmer here, don't know much about math. So go easy ;) ). I recently learned that an audio sine wave is called that way because it is of the shape of the graph of a sine ...
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Does the speed at which sound travel depend on the volume (amplitude) of the sound?

Lets say you have a plank is you hit it once and get t time if you hit is 2x as hard will it travel t/2? will it be the same or will it travel only slightly faster?
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A strange audio phenomenon, could there be a physical interpretation to it?

http://mathoverflow.net/q/165038/14414 Motivation : Here is a motivation as to why this problem is so important. Let $f(t)$ be an audio signal. We can safely asume it to be bandlimited to 0-20kHz as ...
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693 views

Dispersion of Probability Wave Packets

A picture in my text book shows a three dimensional wave packet dispersing, "resulting from the fact that the phase velocity of the individual waves making up the packet depends on the wavelength of ...
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1k views

Sine wave, $\pi$ and frequency

Please explain the relation $\sin(2\pi ft)$ such that how the $\pi$ (which is actually circumference/diameter of a circle) relates with the sine wave which is having a longitudinal vibration?
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How do you find the velocity function of a mechanical wave?

With the form $y(x,t)=A\sin(kx-\omega t+\phi_0)$, there are two variables, How do I find the velocity? I don't know I can apply derivative with two variables.
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368 views

Creation of the Electromagnetic Spectrum [closed]

After seeing this image: http://mynasadata.larc.nasa.gov/images/EM_Spectrum3-new.jpg And reading this: "The long wavelength limit is the size of the universe itself, while it is thought that the ...
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27 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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159 views

Why we don't use gamma rays, x-rays or ultraviolet to transmit data?

The greater the frequency range of a transmission medium, the greater the number of bits per second it can transmit. In other words, the bigger the bandwidth in hertz available, the bigger the ...
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38 views

$\sqrt{\frac{\omega ^2}{c^2}-k_z^2}$ in cylindrical harmonics

The radial component of the solution of the wave equation in cylindrical coordinates is $$J_\nu \bigg(\rho\sqrt{\frac{\omega ^2}{c^2}-k_z^2}\,\,\bigg).$$ But I always thought that $\frac \omega c$ ...
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How do we know the boundaries of a wavelength?

So the length of a wave is the distance between two compressed regions as shown in this representation of a longitudinal wave: But how do you know exactly where the two points are? Is there a point ...
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1answer
83 views

How sound waves are graphed

I asked a basic question about sounds waves recently and got really helpful answers. I have another question (from the same youtube video) about how different sound graphs are used in real world ...
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1answer
108 views

Wave velocity dependence on frequency

Is the velocity of a wave dependent or independent of its frequency? I cannot figure this out on my own. I've asked friends and they do not know.
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58 views

In order for the occurence of beat, why is it compulsory that $|{\omega_2 - \omega_1}| \ll \omega_1 + \omega_2$?

As A.P.French in Vibrations and Waves writes, The beating effect is most easily analyzed if we consider the addition of two SHM's of equal amplitude: $$ \mathbf{x_1} = \mathrm{A} \cos{\omega_1 .t} ...
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Surface waves on Dr. Miller's planet

In the movie 'Interstellar', the crew land on a water world orbiting a black hole. The gravity is greater than that of Earth and there are huge surface waves present in the ocean that they land in. ...
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316 views

Why does sound become louder and increase frequency if I give it a narrow path?

If I put my hand over the speaker of my phone like in the picture, I can clearly hear my music amplified, why does this happen? The only cause I can think about is the fact that all the intensity ...
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137 views

about to create a standing wave

I think partial of this question being asked before but I have some other doubts.As shown in this post how to add two plane waves if they are propagating in different direction?, reading the third ...
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193 views

Symbol in energy formula vs amplitude

Can someone tell me what does the symbol mean in the formula for energy compared to amplitude? Looks like a partial infinity sign, almost like a fish symbol.
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1answer
67 views

What happens to light at sharp points? [closed]

At the tip of the sharp point shown, what will happen to light incident on it. This curiosity was invoked by a friend and also my childhood of watching shiny pointed swords in cartoons. Original ...
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1answer
140 views

The inverse square law of sound through solids?

We all know about the inverse square law of sound. In short the power of the wave will get evenly spread on an ever increasing spherical expansion and this will dissipate the power of the wave at a ...
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413 views

Why can't light waves bend? [duplicate]

Assume that you fixed a speaker to an inclined pipe as well the torch. You can hear sound from the other end of the pipe, but can't see the light from other end of the pipe, why?
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142 views

Does the transmission axis matter for sending polarized light through polarized glass?

If I have polarized light and I send through only one polarized glass plane, does the transmission axis matter, or will the intensity be halved no matter what.