# Questions tagged [waves]

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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### Can a system be engineered to cause a standing wave resonance with gravity waves

Can a system be engineered to cause a standing wave resonance with gravity waves? It appears that gravity waves can be reflected. Do Mirrors for Gravitational Waves Exist? Stephen J. Minter, Kirk ...
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### 3 waves, calculate time of collective period?

I have 3 sinusoidal waves. Frequencies 1.3, 0.8 and 1.5 Hz. They all start at zero amplitude, at the same time. How do I calculate the time it takes for my waves to meet at zero amplitude again, and ...
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### Graphing dispersive wave packet in Desmos [on hold]

I want to find a way to graph a dispersive wave packet using a graphing calculator app such as Desmos. The above is a graph of a non-dispersive wave, which is pretty easy to represent on a Cartesian ...
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### Does a wave blue-shifted by the doppler effect increase in energy? [duplicate]

A wave is blue-shifted by the doppler effect. This increases it's frequency, so this should also increase it's energy as per the equation E = hv ? Therefore does the wave increase in energy from the ...
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### Paraxial approximation - time varying

I want to reproduce the results of a paper I am reading. In the paper, authors use paraxial approximation. My question is: in the potential V, I can put a time dependence of space? Or the paraxial ...
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### What does phase velocity physically represent, and why can it be superluminal? [duplicate]

Phase velocity is defined as $v_p=\frac{\omega}{k}$ and is described in various textbooks as being the speed at which the phase of a wave propagates. If you have a wave train that is modulated by an ...
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### I was wondering if the mass of an object can be measured by the effect it has on a body of water if it was dropped from a certain height? [duplicate]

The question: Height of Water 'Splashing' asks about the height of the splash when an object is dropped into water, but there are other parameters that can depend on the mass and velocity of ...
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### Relationship between Material type and Acoustic Reflection Degree

I have a 1.8mm and a 1.5mm thick surface of polypropylene and I'm beaming a pressure wave at it, what percentage of the wave's intensity/pressure (in decibels) gets through and what percentage is ...
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### Phase difference between displacement wave and pressure wave in longitudinal waves

As the Mathematical treatment yields, the pressure wave leads the displacement wave by $\frac{\pi}{2}$. But I want to ask why is it so? According to me, supposing if the displacement wave is a sine ...
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### Do clouds reflect radio waves?

Do clouds reflect radio waves? Specifically, those waves used in radars. And, what kind of matter refracts or reflects radio waves?
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### Could ultrasound pings and triangulation really help de-scatter diffuse red light for imaging?

Does the science explanation in the latest OpenWater TED talk make sense in principle? The claim involves taking advantage of the doppler effect. Could someone give a more detailed explanation as to ...
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### How to visualize the angular frequency in SHM?

Can anyone define how can i visualize the angular frequency(ω) in a SHM y(t)=R sin(ωt+ϕ) (where ω=2π/T).Bcoz we can visualize frequency(f=1/T) as number of times the process is repeated in 1 sec so ...
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### Propagation of mechanical waves in vacuum

It is known that, while electromagnetic waves can propagate in vacuum as they do not need a medium, mechanical waves (e.g. sound waves) cannot. However, vacuum has vacuum fluctuations, where (virtual)...
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### Waves in rotational motion

If a chain is spun at high speed and let go will that spin on the ground without collapsing, why and how ? If due to a small bump on the road the spinning chain develops a transverse wave what is the ...
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### Total intensity of fiber modes

Is it correct to write the output intensity of a multimode fiber resonator as the linear sum of the intensity of the individual modes? The complex amplitude transmission of a fiber resonator can be ...
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### Why aren't maximums at 1 wavelength for single slit interference?

I can understand why there are destructive points in single slit interference. It is because the path length difference between the "pairs" of rays have a path length difference of $\lambda/2$. What I ...
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### Amount of pressure embodied by a pressure wave (sound)?

I'm looking into a way to calculate the pressure by which a sound wave at close proximity to the target object impacts. My research led me to this physics site (http://hyperphysics.phy-astr.gsu.edu/...
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### Waves velocity for a standing wave of a string

I have done a laboratory experience to determine the speed of propagation of a wave in a vibrating magnetic string. To calculate the frequency (f) of oscillation I used an oscilloscope that calculated ...
2answers
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### Why is the speed of sound in air constant (relative to temperature) when the wave speed formula is Vwave = fλ? [duplicate]

By the logic of the wave speed equation, shouldn't a 1000 Hz sound travel twice as fast as a 500 Hz sound? I know it doesn't, but why not?
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### Optical fibers field analysis, $\phi$ dependence not considered

In optical fibers, the core (with $\varepsilon = \varepsilon_1$) is usually represented by a cylinder of radius $a$, whose axis coincides with the $z$-axis in cylindrical coordinates. The cladding is ...
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### Is the energy of an electromagnetic wave, in electron volts, an 'average' or a 'peak' value?

Since EM waves oscillate, is the energy given in eV an average or maximum value? In a related question, can a detector (of whatever sort) 'miss' an EM wave if the amplitude is at a minimum when it ...
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### Electromagnet produces sound from hollow pipe

I have wrapped around a 80cm metal pipe some copper wire and attempted to produce an electromagnet. The electromagnet works nonetheless from the extremities of the metal pipe a sound is being produced ...
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### Can you change the wavelength of light keeping frequency constant and can you do the opposite as well? [duplicate]

Can you change the wavelength of light keeping frequency constant and can you do the opposite as well? I understood the basics but please don't hesitate to go deeper into the concept. Also, If you ...
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### Resource recommendation for SHM & Wave [duplicate]

I am looking for good resources or books on Simple Harmonic Motion and Wave that doesn't require any prior knowledge of those topics. Books that consist even the derivation of even the very basic ...
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### Examples of non-sine waves? [closed]

What would be a non-sine wave? AFAIK, all sound is a sine wave, equally to waves on the sea. What would be a common example of something in nature that's a wave but not a sine wave? Or, would we have ...
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### How to visualize double-slit interference w/ object creating path difference?

A thin flake of mica (n = 1.58) is used to cover one slit of a double-slit interference arrangement. The central point on the viewing screen is now occupied by what had been the seventh bright ...
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### How does the electron know to “release” the photon at the same angle at which it got absorbed? [duplicate]

This is a quote from Wikipedia: In classical electrodynamics, light is considered as an electromagnetic wave, which is described by Maxwell's equations. Light waves incident on a material induce ...
3answers
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### Why does sound not move through a wall? [duplicate]

I'm learning a bit about sound and was wondering: If the speed of sound is determined by the amount of matter the source is surrounded with, why doesn't it go through a wall? Example: Speed of ...
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### Why are there rings (halos) around street lights? Especially when it's foggy

I was in a car that was turned off last night for some time and the windows became foggy via condensation (moisture droplets building up on one side of window). Looking outside, I could see that ...
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### Which waves are produced during tuning fork vibration? [duplicate]

In my book, it is written that transverse waves are produced during physical motion of tuning fork. But vibration of tuning fork produces sound which are compressional in nature . Please tell me ...
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### Chladni Plate subjected to different waves

A Chladni plate consists of a flat sheet of metal, usually circular or square, mounted on a central stalk to a sturdy base. When the plate is oscillating in a particular mode of vibration, the nodes ...
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### Will tsunami waves travel forever if there was no land?

If there was no land for tsunami waves to collide with, can the waves travel around the globe for forever?