Wave propagation Definition and 87 Threads

Hello, I am confused as to how to think about sound pressure and the distance from a sound source. Let's assume that a sound wave is omnidirectional and propagating away from a source in a sphere. We have the following two equations: Pressure = Force/Area Intensity = Power/Area Many texts...

Hi alltogether, I have been confused about a certain topic of EM wave propagation: it´s clear to me that E and M field are perpendicular to each other (I know Maxwell´s equations well). But: sometimes you can find on the internet that both fields are in phase...

Imagine a long deformable rod which has just been hammered on the top end (the bottom end is clamped to Earth). Consider a time interval $dt = t_{2} - t_{1}$ in which the pressure wave is traveling somewhere within the length of the rod (meaning some portion of the object has already "felt" the...

Assume that we have a 1.5 km x 100 cm^2 long straight pipe, totally inelastic and full of water. From time t = 0, a pressure of 300 000 Pa is continuously applied to the water with a piston at one extremity. This correspond to a force of 30 000 N on the pipe cross section in the direction of the...

$$\int_{-\infty}^{\infty} \frac{e^{-i \alpha x}}{(x-a)^2+b^2}dx=(\pi/b) e^{-i \alpha a}e^{-b |a|}$$ So...this problem is important in wave propagation physics, I'm reading a book about it and it caught me by surprise. The generalized complex integral would be $$\int_{C} \frac{e^{-i \alpha...

Summary:: A plane wave incident upon a planar surface - determining polarization, angle of incidence etc. 𝐄̃i = 𝐲̂20𝑒−𝑗(3𝑥+4𝑧) [V. m−1 ] is incident upon the planar surface of a dielectric material, with εr = 4, occupying the halfspace z ≥ 0. a) What is the polarisation of the incident wave...

The problem I am having is "What can you conclude about wave prorogation in SR given the results?". The best I can come up with is that the number of wave planes N crossing a section of spacetime in either frame is the same. The section may be bigger or smaller depending on which frame you're in...

I am uncertain if this belongs in the differential geometry thread because I don't know what area of mathematics my question belongs into begin with, but of the math threads on physics forums, this one seems like the most likely to be relevant. I recently watched a video by PBS infinite series...

Outside of QM, do perfectly linear waves really exist in nature? I am referring to just those waves that also have dispersion - in which the wave components have differing phase velocities. ... or are we just using the mathematics of linear systems to approximate nonlinear systems? Thanks in...

Homework Statement Use Maxwell's equations to elaborate an coherent explication of why electromagnetic waves propagate independently of the source that produces them. Homework Equations Maxwell's equations in vacuum: ##\nabla * E=0## ##\nabla * B=0## ##\nabla \times E = -\frac{\partial...

I noticed HF radio waves travel farther and easier when the sun is out rather then during the night. Why?

Homework Statement Given the following expression $$ \Psi(x,t) = A cosh(36 x^2 - 12 x t + t^2)$$ Determine whether this is a traveling wave and if so what is its propagation velocity and propagation direction? Homework Equations Wave equation $$ \frac {\delta^2 \Psi(x,t)} {\delta x^2} =...

Homework Statement An E field with f = 2.45*10^9 Hz passes through a material with the following properties e_r = 10 u_r = 1 sigma = 1 (S/m) The Incident E field has peak magnitude of 300 V/m at the air to surface boundary. (a) *solved* Find the incident power density at the material...

Hi, I'm a second year undergrad and we've covered the heat equation, \begin{equation} ∇^{2}\Psi = \frac{1}{c^{2}}\frac{\partial^2 \Psi}{\partial t^2} \end{equation} and the wave equation, \begin{equation} D∇^{2}u= \frac{\partial u}{\partial t} \end{equation} in our differential equations...

speed? This question emerged in my mind while studying a discrete and continuous mathematical model of a falling slinky. In the discrete model, we suppose an instantaneous interaction between mass points at a distance, so the action propagates through the chain of mass points with infinite...

I'm confused about energy driven by a wave. Consider a sinousoidal wave moving in a rope. Each element ##dm## of the rope follows a simple harmonic motion in time. That means that the mechanical energy ##dE=dK+dU## of the element ##dm## is constant. Nevertheless on Halliday-Resnik-Krane I...

Hello Everyone, my question is that what's the formula or equation to find flexural wave propagation speed along the beam?? Please guide with this, I am kind of stuck in this problem. Thanks in advance,waiting for the response...

Homework Statement Based on wave attenuation and reflection measurements conducted at 1MHz, it was determined that the intrinsic impedance of a certain medium is , and the skin depth is 2m. Determine: a) The conductivity of the medium b) The wavelength in the medium c) The phase velocity...

Hi... If we consider propagation of sound through a medium other than vacuum, we mean, when sound is produced by a vibrating speaker diaphragm, it gives periodic jolts to the molecules and atoms present in the medium or air. These "pushes" are transferred to all adjacent atoms until finally few...

If waves require a medium or some kind of force carrier to propagate, how exactly do matter waves propagate?

Hello! In this previous post, most replies point out that it is not possible to predict the angle of refraction (and so the frequency) at a certain interface, given the wavelength of the original signal. In particular, But when dealing with optical waveguides, it seems to be different. I am...

Hi, I'm trying to make sense of a wave propagation problem. It's a 1D problem, modelling propagation of density perturbations which travel like waves in a fluid. The problem is governed by the mass and momentum equations and density is related to pressure using the bulk modulus of the fluid...

I'm a little rusty on my physics, so here's the hypothetical: Put HMX prima cord in a long pipeline , say 1000m. If you detonate the prima cord and the pipe has a 3" ID, would the blast wave outrun the HMX detonation velocity of 9100 m/s. If you reduced the ID of the pipe, is there a certain...

Homework Statement Suppose a person is fishing and is bobbing the fishing pole in constant intervals, there are 2 fish in the water located in the same distance L from the fishing pole (the source of the wave). Suppose also the water is moving from A to B. Which fish will feel the wave first...

Before I start, I apologise for the information dump that is to follow. I don't expect all questions to be answered or all models to be addressed; I simply feel it is appropriate to provide the community with my current knowledge and stage of research so you may not have to search for it...

In contemplation and research regarding another thread's question about the asymmetry of doppler shift wrt the medium, I find myself trying to imagine two people talking... or perhaps better yet matching pitch. In still air with both people facing each other at ten paces of course they would...

I read somewhere that for a wave traveling in a medium a particle (of medium) "gives"(I am not sure if that is the right word) energy to adjacent particle.Is this correct? And if it is why and how does this transfer take place? Also what role does inertia of particle play in wave propagation?

Hello, I'm stuck on how to find the propagation velocity of the signal in the Line as stated in Question C on the attached image below. 1. Homework Statement Table one (in the attached image) shows typical values of Z and Y for an overhead line and underground cable. Please note that this is...

Im a mechanical engineering student currently, with a third year project of simulating ultrasound propagation through the abdomen. Currently i just want to simulate it going through muscle with no obstacles. I don't really understand where to start, I have formed some equations based on the wave...

I'm trying to get my head around radio wave propagation in conductive media such as water, saturated rock, etc. What I know is that propagation is poor but better at lower frequencies and this has something to do with "skin depth". I have read what I can on skin depth but I struggle to relate it...

Hi I wonder if anyone could advise how a radio wave would propagate around a metal object? Basically, I have a GPS antenna and due to mechanical issues the antenna is obscured by a mounting screw that sits in front of the antenna by about 2~3cm. I understand that the radio wave would become...

Hello, We read very often that wave propagation électro-magnetism is the result of an interaction between electric field and magnetic field. However, Maxwell's equations are not causal. These equations have no delay between electric field and magnetic field, they simply pose relations...

Hello everyone, I am going to do a paper that has something to do with wave propagation in a medium, but I am new in this area, so can you guy suggest any book or paper on introduction to the propagation of wave in fluid, my have a solid background in mathematics and mechanics , thank you very much

I want to understand what exactly is Maxwell's theory of wave propagation and what is its physical intepretation?

Hi I am very confused at determining the type of elastic wave in a vibrating body. For example, an elastic solid is flexuraly vibrating in one of its resonant mode. There should be elastic wave excited from this vibration. But, my question is which wave will be excited through it...

Hello everyone. I'm really struggling to simulate a cavity problem. My goal is to be able to know what's going to happen if i introduce spatially dependent phase inbetween mirrors of a cavity that supports certain transverse modes. Well, i believe solving for eigenmodes of a cavity is...

Whats the effect of shrinking and stretching of space on the propagation speed of electromagnetic waves. This is in reference to the direct correlation of the propagation speed to the fundamental properties of empty space viz. permittivity and permeability of free space. Do the permittivity and...

Dear all, I am a newbie in electromagnetic wave. Can you educate me, what will happen when an electromagnetic wave is blocked by a piece of flat metal placed in front of it? My intention is to build a thermal chuck using peltier for to measure femto amps from my device. I am worried if...

I am currently studying AS level physics and we have just started the waves module. When describing light as a WAVE our teacher is telling us that particles are oscillating 90 degrees to the propagation of the wave. What is acting at right angles to the propagation of the wave? As far as i was...

Can anyone tell me how light waves propogate. Will a photon have a trailing cone?

I am studying the vibrations in a coil spring, and want to confirm with others that my derivation is correct. I found that for small oscillations the spring is described by the 1-D wave equation, with wave speed k*l^2/m. where k is the spring constant, l is the spring length, and m is the...

This is my first post and I'll admit I probably don't even know enough to be dangerous. Any how what I have is a a 3' long 6" dia tube that is functioning as a muffler for a boat. It has two 4" dia inlets mounted perpandicular to the length of the tube at 28" on center and two 4" oulets mounted...

Homework Statement A wave is driven at z=0 with constant real frequency ωr propagates in the z direction, for z>0 the amplitude varies as: A = A_0 e^{i\omega_r - ikz} where k is complex k=k_r - i k_i if a wave with spatially constant amplitude and purely real wavenumber kr were...

Hi I can't proceed imagining the matter after this point... For a propagating wave: The medium particle gains energy to move.. Question 1: what makes the particle to move up or down, what is the force acting upon it. The wave sinusoidal pattern shape that travels across the medium...

I was just reading about EM wave propagation and had two questions I would appreciate an answer to. 1-I read how the electric and magnetic fields of an EM wave oscillate sinusoidally and perpendicular to each other and the direction the wave is traveling. Is there any significance or special...

Homework Statement Given the following EM wave propagating in vacuum, find the direction along which the electric field oscillates and the direction of propagation of the wave: \vec{E} = (-3\hat{i} + 3\sqrt{3}\hat{j}) 10^4 e^{i[\frac{\pi}{3} (\sqrt{5}x + \sqrt{5/3} y10^7 - 8.1246 *10^{15} t]}...

Hello, why an electromagnetic signal propagate as wave? Wouldn't be more normal that electron travel in a beeline? Thank you.

Why do transverse waves propagate through solids , while logitudinal waves can only propagate through fluids?? I'm still confused about this

Would gravitational waves propagating through space-time at the speed of light be affected by the curvature? Or are they independent? Why does the spinning of a binary pulsar cause a gravitational wave when there is no change in mass other than the loss of photon energy? Doesn't this object...

I am modelling a radio wave propagation simulator for a Wifi at 2.4 Ghz. I know that the refracted index of glass for light is around 1.5, how do I translate this to a 2.4 Ghz radio wave. And what about other materials, such as concrete, brick wall etc. Thanks.