Waves Definition and 1000 Threads

like in sound waves pressure varies(oscillates) and in light electric and magnetic field oscillates

Hi, i came across this video on BBC yesterday: <link to video deleted> Now I wonder how this stuff works in detail? Is it the carrier wave or the multiplexer signal of the phone? best regards

Hello! So if I want to describe dΨ(x)/dt can I use 1D wave equation?

Can you help me on this question I had for years? Every time I touch two metals together (holding them with my fingers) and place a shortwave SSB radio nearby, I hear clicks and noises on the radio. Why is that happenning? Has anyone observed this phenomenon before?

[Note from mentor: this thread was originally posted in a non-homework forum, therefore it does not use the homework template.] I have been given an equation for the relativistic doppler effect but I'm struggling to see this as a function and then give a first order Taylor expansion. Any help...

This is a quote from an article written by a Phd student in physics in the online magazine Aeon (https://aeon.co/ideas/gravitational-waves-will-bring-the-extreme-universe-into-view): "Consider the properties of the September 14 event: the signal was generated by two objects, each roughly 35...

I understand gravitational waves as ripples in spacetime. As PeterDonis said in an earlier post, " The 4-d spacetime geometry does not have to "propagate" anything; it just is." On the other hand, this is block-universe speak. In this language, verbs that imply change are forbidden. We might...

If the amplitude of gravitational waves, frequency of gravitational waves and the vector potential of magnetic field in surrounding of such waves are known then what would be the easiest way to calculate resultant acceleration of electrons? My above question is based on the various researches...

Hi, I have a general question I was thinking about... So, in a liquid the particles are already very close together and as a result they are, in effect, not compressible. That being said, if we take water, for example, it is possible to compress is slightly. It requires, however, a great deal...

For example, the term angular frequency, it units is radian per second. For phase, it is also measured in radians or degrees, why is that? Why is the math the same when you use angles to describe oscillations?

Hi when i found out about the presence of gravity waves, i first thought 'what happens if they were to be reversed' and then i thought 'what happens to space time in between these waves?' thanks

I know that the electromagnetic waves are alternating electric and magnetic fields. But I don't get why the fields can't stand still and alternate at the same point. Why they always move ?? I would prefer a logical and verbal answer rather than a mathematical answer. But if mathematics helps...

So far I have came to know that when a charge is accelerated the electric field magnitude around the charge changes and the effect is not felt instantaneously. The change in magnitudes of electric and magnetic field travels outwards at speed of light creating the so called EM wave. So the EM...

I'm at an internship and I saw a container labeled ultrasonic gel, which is used to prevent air from coming between a scanner and the human body. This is necessary because apparently ultrasound doesn't travel through air well. Why is this? (don't say because the density is low, because I will...

andrewkirk submitted a new PF Insights post Acoustic 'beats' from mismatched musical frequencies Continue reading the Original PF Insights Post.

Hi I am currently writing a sci fi book for children, and I wonder what happens with a spacecraft if it sails through powerful gravity waves? Does it have any consequences for the ship/crew at all? How abundant are gravity waves in space if you are sailing between stars or galaxies? Thank you!

I have been trying to find a method to predict the polarization effects of a plasma with a B Field on low frequency waves. From Chen's Intro to Plasma Physics and Fitzpatrick's Plasma Physics I understand the development of the dielectric tensor and calculation of dispersion with the B field but...

Hello, I would like to ask, if somebody knows anything about comparison post-Newtonian approximation of gravitational waves and these which were detected. Or generally post-Newtonian predictions vs. facts found in detection. I tried find some article but I didn't find. Please let me know what...

- What exactly is the equilibrium of the waves that is shown on graphs? My understanding is that the oscillations are in the strengths of the field, and different sides of the equilibrium represent different directions of the fields. However, I feel as though this contradicts itself in some...

Homework Statement A rope has an end fixed and the other is passing through a pulley and has a body attached to it. The fondamental frequency of the rope is initially ##f_1=400 Hz##. If the body is then put in water the fondamental frequency of the rope becomes ##f_2=345 Hz##. If the linear...

So we know that in GR electromagnetic waves have their trajectories effected by the gravity of stars and planets. But how about gravitational waves. Are their trajectories altered by gravity? If so, would this imply that gravitons are self-interacting if they exist?

I read this statement from Lenard Audio. "When a large signal spike is created by un-plugging or plugging in signal leads, or when a pre-amp valve is driven hard into distortion (guitar amps), a large non-symmetrical square wave may cause a temporary DC Voltage to appear across a coupling...

Acoustic waves started right after the end of inflation. But on the other hand I always read that the first perturbations reentered the horizon after ±50.000 years. These two fact I cannot cope. A reentering of perturbations at different times also don't go with the synchronicity of the waves...

So I have basic knowledge of radio waves and how they work but how does an amplifier boost the signal? Does it just make the waves stronger (if so how) or does it effect another aspect of the radio wave? Thanks in advance for the assistance.

How are the intensity of a sound wave and the Doppler shift of frequency related togheter? That is, if the source or the observer are in relative motion, how does the intensity change? For a sound wave $$I=\frac{1}{2} \rho \omega^2 A^2 c=2 \pi^2 \rho f^2 A^2c$$ (##c## is sound speed, ##\rho##...

Think at a cop car with a siren that moves with a velocity Vc, it emits a sound with a velocity C Now think about a person that doesn't move, in front of the cop car, shouldn't he register that the speed of the sound emited is Vs= Vc+ C? According to the galileian equations (true for v <<c...

Homework Statement You have a device that can measure sound waves only if the frequency of the wave is in the range ##0.8 kHz- 20 kHz##. You have a whistle that produces sound waves at ##21.5kHz##. You ride a bike moving away from a wall, at the same time you blow the whistle and hold the...

Maybe this sounds mad, but does anyone think it would be possible to see wavelengths that are beyond visible light, maybe through genetic engineering or through other technology? There are many animals than can see infrared & UV. Wouldn't it be cool if we could see what radio waves look like?

I've heard of photons being described as a wave/particle duality. But what evidence is there that individual photons behave like anything other than a particle? I can see how photons en masse can display wave/particle characteristics, but what evidence is there that any individual photon...

In standard Bohmian Mechanics, does the pilot wave support counterfactual definiteness? How about other variants of BM, don't they? Can you mention or bring up a site that summarize all variants of BH and whether the pilot wave in each support counterfactual definiteness. Thank you.

Every moving object has a wave associated with it. If a electron is moving with a speed v we can use ##\lambda = \frac{h}{mv}## to calculate the wavelength of the associated wave and thus the frequency can be calculated. This frequency denotes some kind of oscillation. So what is oscillating here?

Homework Statement transverse wave is traveling through a wire in a positive direction of the x-axes. Distance od the wire particles in the motion of the wave can be described as ##y(x,t)=53*10^{-6}sin(188t-3.14x)## Find the ratio of the phase wave speed and maximal speed of the wire particles...

Homework Statement https://session.masteringphysics.com/problemAsset/1383558/3/21.EX26.jpg Make a table with rows labeled P, Q, and R and columns labeled r1, r2, Δr, and C/D. Fill in the table for points P, Q, and R, giving the distances as multiples of λ and indicating, with a C or a D...

I am very confused. Here are a couple of facts I can't connect : Quanta is the Delta of values of energy. Quanta is a packet of energy. a packet doesn't really stop at a finite distance from its peak. The Energy of a wave is the total energy of its quantas.

http://news.mit.edu/2016/second-time-ligo-detects-gravitational-waves-0615 This seems to be the year of black holes, between LIGO, and new theories of black holes being 2D objects instead of 3D masses. Anyway, I thought this was very interesting news and wanted to share :)

I've always read in my Physics textbooks that high energy EM waves like x-rays and gamma rays, if our body is exposed to them for a long time, can damage the skin significantly. However, how does that happen at an atomic level? As far as I'm concerned, the thing that differentiates a high...

Hi everyone... So, I may be putting too much thought into this. But I'm studying for my Ham Radio license, and I was pondering the size of our allotted range of frequencies. The lowest frequency is in the 160 meter range (clocking in at 1.8 Mhz) So, of course I was thinking what other things...

Now, whenever I asked this question, my teachers either responded with a diagram of a wave like this (psst! it doesn't move in real life, I didn't go to Hogwarts.): or often referred to the analogy of water waves (when you drop something in water, the wave goes outward). But when we talk...

(Sorry for my poor english.) I'm just wondering why is it necessary to have oscillating EM fields for life existing on Earth. The sun has a magnetic field (I think a static one), so why it's not enough to life exists? Also, why we and other animals only see the objects if the fields are oscillating?

Homework Statement Here is the seismogram in question: http://postimg.org/image/iu0dozetn/ There are many parts to this question, but I only need help with this one: Measure the S wave arrival time. Homework Equations NA 3. Attempts at a Solution I know that the P waves arrive at 40...

The Michelson-Morley Experiment (as depicted in the scishow YouTube video "The Greatest Failed Experiment Ever") which was used to test for the effects of 'Aether Wind' appears to be almost, if not completely, the same setup as the one used in a gravitational-wave observatory. Why is the success...

Hi, First: I'm pretty sure my question has been asked numerous times, so I'm absolutely happy with links to other threads. I've used search but it didn't come up with satisfying responses, probably mainly because I don't really know what search terms to use. So the question is: How can a...

Hey all, how does one solve sin(ax + by + c) = sin(ix + jy + d) for d and c if you only know the difference between d and c? Any help appreciated, simply arcsin'ing both sides does not work as you get impossible answers in the exact example I had.

An EM wave is nothing but just magnetic and electric fields regenerating each other. Now if a charge oscillates and it produces sinusoidally varying magnetic field which induces an electric field perpendicular to it at the same place.This induced electric field even varies sinusoidally thus...

Homework Statement A person stands in an open space listening to the sound from two speakers. The speakers generate sound with a frequency of 489.5 Hz, the speed of sound in air is 343 m/s. The speakers are 2.00 m apart and the person walks away from one of the speakers along a line that is...

Homework Statement [/B]Homework Equations I honestly do not know any relevant equations for this relationship. Well except f=v/2l. The Attempt at a Solution The only thing I could assume that it was was some sort of error , but I cannot find much material on the topic , so I was hoping to get...

Homework Statement Which waves can have a constructive interference? Homework Equations ∆x=kλ The Attempt at a Solution I think that waves with the same frequency and phase can have a constructive interference. What if they only have the same frequency? Can they create constructive interference?

Hey! I am about to start my Bachelor's thesis about General Relativity. My professor mentioned that my thesis might as well be related to Gravitational Waves. Do you think that it would be appropriate to work on Gravitational Waves for a Bachelor's thesis? Isn't it too advanced? Also, any idea...

Homework Statement A picture of the problem can be found here: https://gyazo.com/a92447dcfebed53d4cbd12fc94300d9c[/B] Homework Equations So, I've already finished part A. For part B, I'm trying to figure out how to equate the two with mass on either side of the equation so that I can solve for...

One of my students asked me the seemingly innocuous question of "how does wind affect the speed of sound?". My immediate thought was that the velocity of the wave would be the vector sum of the velocity of the wind and the velocity of sound waves in still air. However, upon further reflection I...