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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Why doesn't amplitude affect the speed of sound?

I understand why amplitude doesn't affect the speed of the sound AFTER the 'leading compression'. The extra force provided on one stage of the cycle is countered on the other stage. But shouldn't the ...
0
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1answer
55 views

String vibration

In many textbooks an illustration of a vibrating string at a fundamental mode shown (and wikipedia) shown like this http://en.wikipedia.org/wiki/File:Standing_waves_on_a_string.gif). However if you ...
2
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1answer
752 views

What is sympathetic resonance?

When two tuning forks stand near one another and one is excited, the other rings as well. When high notes are struck on a piano, lower notes are also heard. If I understand correctly, this is called ...
2
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1answer
73 views

Light Waves and Light Photons gedanken Experiment

Suppose you have a source of light that emits light with a wavelength of 2 meters, and you set the device to be turned on and switched off alternately. You also set it so that each interval the device ...
0
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0answers
184 views

Instantaneous displacement of a traveling sine wave with an undisturbed starting condition

The equation for the instantaneous displacement of a traveling wave at time $t$, and at any position $x$ along the wave is: $$y(x,t) = A_{max}\sin(kx +\omega t + \phi)$$ But this is only valid ...
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1answer
99 views

Ratio of energy of normal modes of string

Suppose there's a wave on a string represented by fourier series: $$y(x,t) = \sum_{n=0}^{\infty} (-1)^n \frac{1}{2n+1} \sin(nx)\cos(nct)$$ I know the energy is $\propto y^2 n^2$, where $y$ is the ...
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0answers
35 views

Normal modes of two wires fastened together

The problem is to find the normal frequencies of the system formed by two fastened wires of length L, and different mass per unit length. I already wrote the boundary conditions, but I need to know ...
0
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2answers
114 views

Is light electromagnetic waves or quantumn particle waves? [duplicate]

Is light electromagnetic waves or quantum physical particle waves. Or are they the same? Note: My question is specifically how electromagnetism plays into the quantum physics and the double slit ...
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6answers
828 views

How do traveling waves pass through a standing wave node, if the node doesn't move?

I'm having trouble with the explanation that a standing wave in a string is the superposition of traveling waves. The nodes in the diagram above are points where the particles of the string's ...
2
votes
2answers
131 views

Static wave's equation

In my book equation for two advanced wave which created this static wave are $$y_1=asin{\frac{2\pi}{\lambda}(vt+x)} $$ $$y_2=asin{\frac{2\pi}{\lambda}(vt-x)} $$ and equation for static wave is ...
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0answers
31 views

Is light and sound waves interconvertible? [duplicate]

Light is produced when an air bubble underwater is collapsed with sound wave. Why does it happen so?
2
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1answer
87 views

Interference - the shortest way from the point of constructive one to the point of destructive one

So this is a problem from Polish maturity exam. The image shows 2 speakers (G1, G2) and point B. The wavelength of sound coming from both speakers is 0.155 m, and the wave coming from both speakers ...
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1answer
147 views

Baker and Copson “The Mathematical Theory of Huygens Principle” 1987 page 17

In Baker and Copson "The Mathematical Theory of Huygens Principle" page 17, how is this equation derived (after the first paragraph): $ R_0 r sin(\theta) d\theta = R dR $ I don't even know where ...
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3answers
2k views

Do photons occupy space?

Total noob here. I realize that photons do not have a mass. However, they must somehow occupy space, as I've read that light waves can collide with one another. Do photons occupy space? and if so, ...
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2answers
107 views

What is the lenght of the rope?

The $E$ string of a violin has a linear density of $0.5 g / m$ and is subjected to a $80\text{N}$ of tension, tuned for a frequency $u = 660 \text{Hz}$: What is the length of the rope? I know ...
3
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3answers
178 views

Why do tunneling photons outrace their non tunneling counterparts in vacuum?

If we describe a photons with a wave packet, moving towards a potential barrier and E smaller than V, there is a finite chance that it will tunnel to the other side. In this process it is likely that ...
0
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1answer
133 views

What can cause a change in wave's shape - One dimensional wave

what can cause a change in wave's shape of one dimensional wave moving through a rope? It's velocity ? or the wave's length ? What can cause him change his shape.
0
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1answer
102 views

Spring Constant - Waves

I tried to prove that for the same length of spring , a one dimensional wave that moves faster in spring 2 than spring 1, its spring constant will be lower than the spring constant of spring 1. ...
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2answers
98 views

Need help visualising transverse waves

From studying waves I find that I can visualise longitudinal waves where the wave propagates in the direction of the displacement. However I don't understand what causes the propagation perpendicular ...
2
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1answer
94 views

Can the motion of a cracking whip be described as the interference of two waves?

I was watching a whip crack in slow motion and I noticed that the motion of the whip could be described using two different circular descriptions. 1) the user circles the whip around over his head, ...
2
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1answer
46 views

Understanding the displacement of a particle in a wave

I have a question regarding waves and the equation we use to describe their motion. My understanding feels shaky, so i'd like to see if I can get a good explanation/way of thinking about it. The ...
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1answer
72 views

Does sound gets faster when air bubble is supend in water?

Does sound gets faster when air bubble is suspend in water? c = sqrt(K/P) c = speed K = bulk module P = density When air bubbles is homogenized into water the density is lower, so should sound ...
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0answers
50 views

How do I get around the fact that boundary conditions don't apply in the equation's region of validity?

A tight string lies along the positive x-axis when unperturbed. Its displacement from the x-axis is denoted by $y(x, t)$. It is attached to a boundary at $x = 0$. The condition at the boundary is ...
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3answers
227 views

Can a wave possess spin?

Since a matter wave is associated with a particle in quantum mechanics, does the wave spins? I mean, can we visualize the spinning of wave or is it possible that the wave spins?
0
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1answer
143 views

Why the crest of water absorb more light than the trough of water?

I have done my experiment using water ripple to study the behavior of waves. I know that the crest will absorb more light than the trough so that the image created on the white paper sheet appeared to ...
2
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1answer
365 views

Why maximum energy transfer at natural frequency even if max amplitude occurs below $f_0$

This is a paragraph from my book: "For a damped system, the resonant frequency at which the amplitude is a maximum is lower than the natural frequency.However, maximum transfer of energy, or energy ...
2
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1answer
101 views

Tuned Mass Damper

I was learning about the different applications of resonance and one of them is the tuned mass damper used in buildings. One thing I am confused about is as to why the mass attached to the building ...
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1answer
78 views

Properties of 3D waves [closed]

I have a few questions about 3D waves: Are all 3D waves types of electromagnetic radiation? Are all 2D waves mechanical?
2
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2answers
63 views

Can a force applied to a wheel find the fastest way of getting to the other side?

I haven't studied much about this, so if I am mistaken about something please correct me. From what I have seen around the Internet, a force applied to a object takes time to propagate through the ...
3
votes
1answer
746 views

“Derivation” of the Heisenberg Uncertainty Principle

Ok, so I posted this in the mathematics StackExchange, but got no response. The question I outline below is my textbook's "derivation" of the Heisenberg Uncertainty Principle. The "derivation" my ...
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2answers
89 views

Is there just one fundamental frequency?

I read simple definitions of the terms frequency, and fundamental frequency, which defined them thus, Frequency: the number of occurrences of a periodic wave during a second Fundamental Frequency: ...
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1answer
55 views

Reason for the experiment [closed]

Why is the independent confirmation by separate experiments such as important part of the development of the idea of the existence of electron wave?
2
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1answer
175 views

Does timbre consist in pitch and volume?

I read that the physical properties of a sound wave correspond to its audible qualities: pitch, volume, and timbre. However, an oscilloscope uses only two-dimensions to accurately depict the physical ...
5
votes
2answers
532 views

Which solution to the electromagnetic wave equation is the most accurate model of monochromatic light?

When a photon is modeled as a monochromatic electromagnetic wave its electric and magnetic components are usually taken to be sine waves (for example here ...
3
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3answers
553 views

Calculating the mass of a wave of water

I am assuming it is possible to calculate the mass of water if the volume is known. My assumption is that doing this for stagnant water, in a container perhaps, is easy. However I want calculate, ...
2
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1answer
76 views

Is polarization of a wave just a description of its motion in three dimensions?

Since a polarization of the wave is described by complex numbers, we can try to give that mathematical formalism geometrical meaning. With having two different axes, one imaginary and other real, it ...
1
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1answer
533 views

Why does diffraction depend on wavelength? [closed]

We've all heard of the diffraction of radio waves over a mountain and the diffraction of water waves through a gap, but why does this effect depend on wavelength? I'm looking for as simple answer as ...
1
vote
1answer
93 views

Modeling Water Surface Impact

I have a project that is to model the wave equation in a pond due to a pebble being thrown in. The project is quite simple as all we really have to model is the wave equation with an initial ...
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0answers
23 views

What's the proof that the polarization occur s to the electric field of the light? [duplicate]

What's the proof of the light polarization that it happens to the electric field and not the magnetic field? How did Malus discover that the light is polarized although he didn't see the waves ...
3
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2answers
969 views

Why doesn't the magnetic field polarize when polarizing light?

If the magnetic field doesn't polarize does it follow the electric field path of propagation? or does it vanish?
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0answers
51 views

Stationary wave on a string

The problem says: A string lies on the x-axis, and is fixed at $ x=-a $ and $ x=a $. At $ t=0 $ we impose a transversal velocity given by $ a^2-x^2 $. Assuming that the velocity of the wave is $ c ...
4
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2answers
431 views

Do mechanical waves travel in straight lines?

Electromagnetic waves travel in straight lines but do all waves travel in straight lines?
2
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3answers
2k views

How to “derive” the wave equation without refering to strings?

The wave equation in $3$ dimensions is simply: $$\nabla^2\psi = \dfrac{1}{v^2} \dfrac{\partial^2}{\partial t^2}\psi,$$ and the intuition behind this is that at each point of space with coordinates ...
2
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3answers
308 views

Does interference take place only in waves parallel to each other?

The title says it all but I will add some details. I believe that interference takes place only in waves which are parallel to each other. See the picture to understand what I mean by parallel. We ...
4
votes
2answers
278 views

Why are two voices singing the same note louder than one?

Let's say for example: Two people sing the same note (frequency) and volume (amplitude) together. Why is it that the two persons sound louder than they would ...
3
votes
2answers
51 views

Why a minus in the equation of a paraxial plane wave?

paraxial plane wave = $\exp{(-jkz)}$ for waves propagating to the right I can't figure out why it's not $\exp{(+jkz)}$. Any help would be greatly appreciated, thank you.
3
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2answers
106 views

Locations of destructive interference for two spherical waves

I have looked at this, but it did not help with locations. Really this just comes down to mathematical manipulation, which for some reason I fail to see. Here is my paraphrased setup: Consider two ...
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0answers
119 views

Number of wave modes in a cavity

I'm trying to calculate the number of acoustic modes that can exist in a room in a certain range of frequencies. I thought of using the Rayleigh-Jeans formula for the electromagnetic standing wave ...
3
votes
3answers
191 views

When polarized light hits a polarizer, what happens to the polarization which is not transmitted?

It is typically said that in polarization of light only those waves can pass through a polaroid which has a plane of vibration parallel to the axis of polaroid. My question is: what happens to the ...
8
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1answer
646 views

Are small speakers inherently limited to higher frequencies?

I am hoping to build a subwoofer using multiple smaller speakers (165mm) instead of a single larger speaker (380mm). My theory is that the displaced air volume is what matters, not the individual ...