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How Do Soundwaves Move and Influence Specific Particles or Gases? Natural Resonant Frequencies?

If you read this link your questions can be answered . Formation of the inversion layer causes a lack of vertical movement of the atmosphere and the occurrence of long-lasting high concentrations of ...
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1 vote
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Mode expansion of wave function in 1+1D

Hints: The spatial $2\pi$-periodicity (1) and the solution (4) imply that we can separate the lightcone variables: $$\exists c:~~ f_+(\sigma_+ +2\pi)-f_+(\sigma_+)~=~c~=~f_-(\sigma_- )-f_-(\sigma_- +...
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How is it possible to receive 2 pulses from only 1 sent pulse?

@JohnRennie 's answer is interesting, but OP says that the ultrasound pulse is sent at "normal incidence". This implies that the ultrasound first travels in air and, therefore, is initially ...
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2 votes
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How is it possible to receive 2 pulses from only 1 sent pulse?

In solids sound can propagate as a longitudinal wave or as a shear wave and these two waves have different velocities. The speed of a longitudinal wave is: $$ v_p = \sqrt{\frac{K + \tfrac{4}{3}G}{\rho}...
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Virtual photons and slowing down longitudinal wave propagation

2.) Suppose the charge shift in the rod follows a sine movement. Then a longitudinal wave will propagate. Is there a possibility to slow down the speed of this propagation? How is a radio wave ...
1 vote

How does an electron wave move between locations in QFT?

The idea of a quantum field as a bunch of oscillators is really quite bad an analogy if you want to use it to reason about how quantum field theory actually works, see this question and this question. ...
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3 votes
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Intuitive understanding of the unit $kg/s^3$ — the unit of sound volume

Not every combination of base units has a clear physical meaning. The best way to understand any quantity is to look at the equation that produces it. For instance in your case sound intensity $I$ ...
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-1 votes

Double Slit Thought Experiment to Account for the Particles that Don't Go Through the Slits

The root of your question is that you are thinking because there is "interference" particles are cancelling and therefore there should be less of them ....? Electrons are particles and they ...
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Optimal Way for Transmission of Sound from Air to Water

You could try a horn from a horn speaker in reverse. The horn acts as a transformer between the speaker diaphragm and the much lower impedance outside air. The sound pressure is much higher at the ...
1 vote

What does the wave created during refraction look like?

The interference is due to a shift in the phase. There is no change in frequency (assuming ordinary refraction, and not another phenomenon such as fluorescence). An electron bound to an atom can be ...
3 votes
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Double Slit Thought Experiment to Account for the Particles that Don't Go Through the Slits

Do I have the correct rough detection patterns at both A and B in both the W and P setups? Yes (though it would of course be strictly zero where the slits are) Will the total number of detections N ...
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3 votes
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Plane waves in terms of spherical waves in 2D

3D Case: your expansion is wrong The expression you wrote is not right, here is the correct expansion: using spherical coordinates $(r,\theta, \phi)$, there is something called partial wave ...
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1 vote
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What does the wave look like during refraction?

Actually, the wavelength itself decreases when the ray travels into the denser medium, since the speed of the ray decreases and the wavelength must also decrease given the frequency stays constant. ...
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1 vote

How do we deal with doppler effect in $3D$ space?

If $\hat{r}$ is a unit vector pointing from the source to the receiver, then $v_s \cos \theta = \hat{r} \cdot \vec{v}_s$, where $\vec{v}_s$ is the velocity vector of the source. So the natural ...
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How do we deal with doppler effect in $3D$ space?

2D case $$\vec R=\begin{bmatrix} a-u\,t \\ b \\ \end{bmatrix}$$ and $~\vec R~$ with polar coordinate $$\vec R_p=r\,\begin{bmatrix} \cos(\phi) \\ \sin(\phi) \\ \end{bmatrix}$$ with $$\vec R=\vec ...
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Finding electric field of the electromagnetic wave for given magnetic field

From the relation $\vec{B}_0 = (\vec{k} \times \vec{E}_0)/\omega$, you can actually solve for $\vec{E}_0$. To do this, take the cross product of $\vec{k}$ with both sides: $$ \vec{k} \times \vec{B}_0 ...
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Finding electric field of the electromagnetic wave for given magnetic field

Use the Ampére equation and solve for the electric field: $$\vec\nabla\times\vec{B} =\mu_0\varepsilon_0\frac{\partial\vec{E}}{\partial t} \Leftrightarrow \frac{\partial\vec{E}}{\partial t} =c^2\vec\...
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Finding the average displacement of a particle on a fixed position of a mechanical wave for a period

Here's the proof that my high-school physics teacher showed me back in the day, before I had taken calculus: The averages $\langle \sin^2(x) \rangle$ and $\langle \cos^2(x)\rangle$ over one period ...
1 vote

Derivation of Fresnel distance

"As far as I know, the angular width of central maximum is given by 2λ/a and not λ/a." The half-power angular width of the main beam is λ/a radians. That's why it is preferred.
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Extremes of integration with box normalization

Typically we would define our box to go from $-\ell/2$ to $\ell/2$. One reason for doing this is that it makes it easy to consider the parity of functions under reflection about the origin, where $x\...
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How do we know sound pressure squared is proportional to the power in the sound wave?

First, let's consider a pressure transducer, such as a microphone. When we use it to record sound, in practice we are logging a voltage. For a linear system, each increase in pressure results in an ...
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Deriving the group velocity of a wave produced by some basic cosine waves with unequal amplitudes

I have tried to solve this issue with simple trigonometric identities but I couldn't. When the tones have different amplitudes you need to use Fourier analysis. The following link is a perfect match ...
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In double-slit experiment, if one directs coherent light from two sources into each slit separetely, is ridges pattern expected to be seen?

The saying “interferes with itself” is historical and misleading … the modern way is to say “each photon determines its own path”. The photon is actually coherent with the apparatus and that it why it ...
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2 votes

How do you determine the direction of an electric field?

If you aren't familiar with vectors in general, remember that a notation such as: $$\vec{D}=D\,\hat{u}$$ describes a vector $\vec{D}$ with a direction carried by unit vector $\hat{u}$, and with a ...
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In double-slit experiment, if one directs coherent light from two sources into each slit separetely, is ridges pattern expected to be seen?

Let's say we have a red laser and a green laser, pointed at the same area on a color film. Now a red dot on the film is produced by a red photon, which is produced partly (99.9999%) by the red laser, ...
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1 vote
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Are there any example of 3-dimensional mechanical wave that is a tranverse wave?

As Jon mentioned in the comments, phonons in solids have transverse components. To elaborate, just as electromagnetic waves in a cavity are quantized, mechanical waves in a solid is quantized. The ...
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In double-slit experiment, if one directs coherent light from two sources into each slit separetely, is ridges pattern expected to be seen?

Forget photons: interference is a wave phenomenon. It predicts where you will detect photons, but it does not involve photons. You can do this experiment by tuning in to weak stations at night (to get ...
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Anyone aware of a double, double slit experiment?

Multiple diffraction is common in high resolution spectrometers. The waves act like waves all the way through until they reach the detector. It is the detector that performs the "observation"...
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Why antinodes must be present at the free ends of an open organ? (Neglecting end correction)

1D acoustic waves arises from the isentropic linearized Euler equations, namely $\left\{\begin{matrix}\partial_t \rho + \rho_0 \partial_x u = 0 \\ \rho_0 \partial_t u - \partial_x P = 0 \end{matrix} \...
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3 votes
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Why antinodes must be present at the free ends of an open organ? (Neglecting end correction)

Personally, I find it easier to think about sound waves as pressure (or density) fluctuations rather than fluctuations in particle displacement. The gauge pressure has to be zero at open ends of the ...
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What are harmonic waves?

In the world of music... In many different kinds of resonator, the system is capable of vibrating at multiple, distinct modes all at the same time. Most tonal musical instruments are based around some ...
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What are harmonic waves?

Even though it's better to check the definition in the context, I'd use the term "harmonic" for a periodic sinusoidal signal (you get cosine with phase shift), thus a signal that has 1 ...
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Is my derivation of the electric field from a thin wire with changing current correct?

I think i have a solution to this problem. I will use the cgs(gaussian) system. The Maxwell equations are: $$\nabla \cdot \vec{E}=0$$ $$\nabla \cdot \vec{B}=0$$ $$\nabla \times \vec{E}=-\frac{1}{c}\...
4 votes
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ODE solutions for a driven oscillator in higher resonance modes

The full solution is $y(t) = \dfrac{\sin (\omega t) -\omega t \cos (\omega t)}{2 m \omega ^2}$ where $\omega^2 = \dfrac km$. It may not look dimensionally correct but one must remember that there is a ...
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11 votes

ODE solutions for a driven oscillator in higher resonance modes

An oscillating system may have numerous resonances, but not that system! That ODE represents a driven harmonic oscillator with exactly one resonant frequency and, indeed, if you apply an out-of-...
1 vote
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Physical manifestation of mechanical waves for a non-defined value of the cotangent function

Short Answer: Real life would kick in, and the rod would vibrate in a slightly different manner than this theory would suggest. Longer Answer: The wave equation is a mathematical idealization that ...
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Physical manifestation of mechanical waves for a non-defined value of the cotangent function

You would be at resonance. The amplitude of the wave would grow with time to the point at which the linear wave equation is no longer a good approximation.
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Wave equation for a driven string and standing waves

I'd apply Dirichlet boundary conditions on both ends, the driven end with the prescribed displacement, the other one with homogeneous b.c., namely: $u(0,t) = u_0(t)$ at the driven end in $x=0$ $u(L,t)...
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Why is entanglement not explainable by pilot waves theory?

Consider two electrons in an entangled state such as this one: $$|\psi\rangle = \frac{1}{\sqrt{2}}(|p_x,\uparrow\rangle |-p_x,\downarrow\rangle - |p_x,\downarrow\rangle |-p_x,\uparrow\rangle)$$ That ...
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3 votes

Why is entanglement not explainable by pilot waves theory?

I think you might have misinterpreted the video. Towards the end, it says that the water droplet experiments which (many say) resemble Bohmian Mechanics cannot demonstrate entanglement. It wasn't ...
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Condition for constructive interference is that one wave has to be a $\lambda$ ahead of the other

The condition you are mentioning is restricted to the case of two waves that have the same wavelength. These two waves do not have the same wavelength. Constructive interference is a more general ...
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