Waves Definition and 1000 Threads

Homework Statement The problem I have is that we are asked to show the complex relative permittivity of a good conductor is erc = 1 + i(sigma)/(omega*epsilon_0) where sigma is the conductivity and omega is the frequency of an electromagnetic wave in the medium. This is fine, I calculated it...

I want to practice my problem solving skills on waves(and optics) so, I would like to have a good problems book about waves(not a book containing problems-nearly every book contains problems- but a book that is all about the problems). I am looking for a book which has exercises that offer...

Homework Statement Homework EquationsThe Attempt at a Solution I formed a right angle triangle between the arrow downwards,d, and perpendicular line x from arrow. As such, sin θ = x/d. x= d sinθ path difference: d sinθ/λ My answer is C, but answer is B. Where did cos θ come from?

When finding solutions to Maxwells equations we always cosider the case of a plane wave. But are plane waves real/physical solutions we can consider in real life? My guess is not because it is required to propagate infinitely. So why do we use plane waves to solve Maxwell's equations?

I came across this expression for the wave equation: \nabla^2E + \mu\sigma\frac{\partial{E}}{\partial{t}} - \frac{n^2}{c^2}\frac{\partial{E}}{\partial{t^2}} = 0 My question is what kind of medium is it for/where did it come from?

In charge density wave systems in paper http://journals.aps.org/prb/abstract/10.1103/PhysRevB.37.10055 subharmonic steps are detected in experiments from the differential resistance ##\frac{dV}{dI}##, instead of from ##I-V## characteristic. Since the charge density wave resistance is shunted by...

Not sure if this is an engineering or physics question, but here it goes: I'm trying to wrap my head around the pressure field caused by waves. I'll recap to so anyone can check if I have made any incorrect assumptions: If we ignore atmospheric pressure, the pressure in the water has a...

" Thus according to Maxwell, light waves are associated with changing electric and magnetic fields; changing electric field produces a time and space varying magnetic field and a changing magnetic field produces a time and space varying electric field. The changing electric and magnetic fields...

Not much more to my question than the title - I imagine that if they do exist they are probably lossy, else with all the potential wave generators that have been in existence generating waves for billions of years there would be lots of waves bouncing all over the place and they would be readily...

I'm calculating a problem with motion equations. I need to use a motion equation for a sound wave (this is a simple problem of kinematics (fall of a rock) and I don't have any background about waves or harmonic motion)... So then I started to think... For intuition I know that sound doesn't have...

I'm not sure exactly how to phrase this question, but I was thinking earlier about electromagnetic waves being absorbed by atoms and 'slowing down' the speed of light. Do gravitational waves propagate slower when blocked by, say, a really massive object? In the same way that light slows down...

Mirage: we consider the x-y plane describing vertical y and horizontal x directions, with an inhomogeneous index of refraction n(y). In this case, using calculus of variations, Fermat’s principle for the trajectory of a ray of light may be re-written as n(y)/√1+(dy/dx)^2 = A. Where A is a real...

The only man-made water waves I can think of are artificial waves in specialized swimming pools. If the wavelength of the water wave is W, does the instrument generating these waves have to have dimensions on the same order as W? In other words, if you have a small object, can you generate...

I am currently in my second year of a bachelor of science with a major in physics. The class I am taking is notorious for being hard and the professor is very hard to understand (understanding the material, not what she's saying). The class is all about oscillations and waves. The textbook is...

Is it theoretically/mathematically possible for light waves to be red-shifted so much that it's amplitude is equal to zero?

The photography book I have talks about waveforms, but it doesn't do a good job of explaining them. So, here's my understanding from the book and google searches (it could be unbelievably wrong.) In an isotropic homogenous medium, light will spread out in all directions, essentially forming a...

Homework Statement Do waves travel faster in dense or less dense mediums? As a wave moves from a less dense to a denser medium at a boundary end what properties change? (Wavelength, speed, frequency, amplitude...) If waves travel faster in solids then why do we hear better through air, and if...

Homework Statement A backyard pool is 14.5 m long. For fun Sally uses a board to create waves. Sally investigates the effect these waves have on Susan who is floating on another board near the middle of the pool. Sally notices that the waves travel with a speed 6.2 m/s. a) If Sally moves the...

A jet flying directly over you at an altitude of 3300 m produces a shock wave. The angle of the shock wave is 43 degrees. How long will it be until the sonic boom reaches you? How far does the jet travel during this time interval? I know that I can figure out the second part of this problem if...

You want to build a portable device that can detect pirate radio stations broadcasting at about 50 W of power a few miles from your beachfront home. You have a 0.60-m diameter bowl you might use as an antenna dish, but you are worried that your amplifier input will require a signal of at least...

If a mass bends space-time somehow and then I nudge it, the bend changes. This distortion of space-time bend is supposedly expanding at the speed of light and could be called a "gravity wave" that carries energy. Why is this wave not the distortion that creates a "graviton" like EM and photons?

in transverse wave (traveling pulse) when a particle move down it has maximum velocity at equilibrium point , why it stop suddenly at this point?

the news media has published the fact that there has thus far been no detection of gravitational waves as predicted by GR. eg Parkes Pulsar Timing Array found nothing after 11 years. If there are no gravitational waves, then GR is wrong. a common argument for gravitons is that there are...

Homework Statement Initially your receiver is positioned at a distance of 8.4 cm from the goniometer and recording a maximum intensity. You move it through 10 minimums in the intensity and then stop at the next maximum intensity. The receiver is now a distance of 27.3 cm from the goniometer...

I understand, from my textbook, that certain frequencies of sound (depending on the length of the tube) will reflect off the interface between the air in the tube and the air outside, that this interface is a discontinuity. But in all other cases where discontinuities caused (partial)...

So I was thinking that radio waves travel at the speed of light, approximately 300,000,000 m/s.I was wondering how much time it would take if the average distance from Earth to the Moon is 384,000 km.

Q. Is the following a correct definition of waves? “Waves are vibrations that transfer energy from place to place without matter (solid, liquid or gas) being transferred. Think of a Mexican wave in a football crowd - the wave moves around the stadium, while each spectator stays in their seat...

Homework Statement A block weighing 9.81N oscillates on a plane inclined of 60 degrees attached to a spring whose constant point is k=100N/m and the length is to equilibrium l0 = 0.6 m. While the block goes to the top losing speed , a timer is started ( to t0 = 0) when the block passes through...

Homework Statement " Two traveling waves are generated on the same taut string. Individually, the two traveling waves can be described by the following two equations: If both of the above traveling waves exist on the string at the same time, what is the maximum positive displacement that a...

The question is: You drop a coin down a well. After 3.2 seconds you hear the sound of the coin splashing into the water surface below. How far below lies the water surface in the well? After doing all the work the answer comes out to d = 46.0 m. However, when solving for "d" I had to solve a...

Homework Statement how do you add two waves with the same frequency but different phases? E1 = 7*sin(omega*t + 70degrees) E2 = 13*sin*(omega*t + 65degrees)[/B]Homework Equations Er = E1 + E2[/B]The Attempt at a Solution I know how to add waves that only have one phase, i.e. E1 =...

If you seal a loudspeaker at the end of a tube and close the other end of the tube you will get standing waves; but what are the boundary conditions at the speaker for the sound pressure wave? Pressure =0 or Pressure = MAX? I find no mention of this in the literature. To find out I performed a...

I was reading about a process called up-conversion mentioned in Robert Boyd's Non-Linear Optics. It is essentially a special case of sum frequency generation (in sum frequency generation, two waves of different frequencies are sent into the crystal, and out comes a wave with a frequency equal to...

Homework Statement A simple harmonic wave train of amplitude 3 cm and frequency 200 Hz travels in the +ve direction of x-axis with a velocity of 20 m/s. Calculate the displacement, velocity, and acceleration of a particle situated at 50 cm from the origin at t = 2 s. Homework Equations I used...

I am given three sine waves with individual frequency being 10 Hz, 50 Hz, and 100 Hz. What is the frequency of the following : y(t) = sin(2π10t) + sin(2π50t) + sin(2π100t) Is it simply 100, the LCM of all the sin waves? If not, How to calculate the frequency of y(t) ?

I've recently learned about EM waves. One thing I find hard to really get, is how the E and B fields are constantly "generating" each other. I think maybe the key for this is in the following equations, obtained from Maxwell’s equations in vacuum : (source...

So,the thing is i want to convert distortions generated in two RF signals in Electric energy. Actually i want to store it and then use it. example- Charging my smartphone. So what will be the basic requirements for me to do so!

There are many waves and oscillations books out there that also include Fourier analysis but very few give the subject a thorough treatment, they just pass it in a few pages. If anybody has any sources(particularly books) that have Fourier analysis and particularly Fourier Transforms, I would...

I need help explaining that this assumption is not correct or correct: A product uses Radio waves to turn on a LED. Radio waves can be a form of electromagnetic fields therefore, a Hall Effect sensor could be used in this device to turn on that LED.

The first postulate is perfect, the laws of physics are the same for all uniform inertial frames of reference. In fact the second postulate is perfect as well the speed of light is constant in all uniform inertial frames of reference. But here is my problem with it, the speed of any wave is...

The book is expensive, so I want a book like Bekefi's and Barrett's Electromagnetic Vibrations,Waves,Radiation. Preferably at a higher level than this book. Thank you!

After a Compression (Oblique) Shockwave during supersonic flight, the air speed (Mach number) is always reduced. I was wondering if an aerodynamic shape could be created to increase the speed of the affected stream to a Mach number greater than the freestream Mach number. I am looking for an...

-- Hi. When a gravity wave pass Earth then the time goes a little faster and/or slower. Can there be a phenomenon in the universe that create a gravity wave that is so curved, that when it pass earth, the time stop or go infinitely fast? Regards Magi --

I want college-level problems books on the following physics topics: 1)Quantum Mechanics 2)Electromagnetism 3)Classical Mechanics 4)Thermodynamics (and Statistical Mechanics) 5)Waves 6)Special Relativity

A string has one end tied to a wave generator, and the other tied to a fixed position,. It takes the wave 0.10 seconds to travel 4.5m. Withing the same distance there are 3 complete loops. Find the frequency of the source. Pretty generic question. But I keep getting stuck at trying to find the...

We know that in normal mode all the particles of the system vibrate with same frequency but if take a string fixed at both ends and make it vibrate in one of the normal modes in some cases we see nodes being formed at certain points and we say these are the points with zero amplitude but since...

Hey Everyone. I am new to this forum, so first of all greetings to everybody. What are your thoughts on the below idea..? Is it possible to make the pressure impulses created by a Supersonic Aircraft to travel faster than the speed of Sound? I know that the pressure impulses during a Supersonic...

Hi all, I came across this figure in a textbook. Simple stuff, but can get tricky: I don't understand why the sign convention flips upon entering the barrier (region II), but I guess the book is correct and that I should just take it as a fact. If anybody has a reasonable thought to add...

Today I was presented with dispersion in my introductory physics class. Before this topic was presented we were told of two important rules for waves: 1) The speed of a wave is dependent on the medium in which it travels and 2) the frequency of wave does not change when going from one medium to...

Hello to anyone who reads this, and good day.I am an intermediate C++ programmer and I am looking to understand how to stretch or lengthen audio waves as long as I want without distortion. What I mean by "stretch" is to prolong the duration of every instance of sound. As of now I am assuming...