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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How does Huygens Principle incorporate the unidirectional property of a traveling wave?

I was reading French's Vibrations & Waves where he discusses Huygens-Frensel Principle. The principle talks about how secondary sources give rise to secondary wavelets to form the displaced ...
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Does background noise while strumming a string affect the frequency recorded?

Does the interference of the waves cause instances of destructive interference where there is no amplitude. Technically the wave is still there although its amplitude is 'cancelled' out but those ...
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15 views

What justifies adding phasors' vertical components

I learned that, when superimposing two waves on top of each other to calculate the resulting wave's amplitude, it's helpful to use phasors. From what I gathered, phasors are vectors originating at the ...
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Refraction, diffraction or reflection of human voice

Why is possible to hear in an open space someone's voice even if he's not facing me? Is it because of refraction, diffraction or reflection of the sound wave?
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1answer
27 views

Wave equations - how to get a real solution from imaginary roots

Im trying to follow the derivation on how to solve Laplace equation used in my fluid dynamics course. We are trying to solve for the velocity potential in potential theory. So far we have this: ...
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21 views

Which wave works best?

I heard that gamma waves have the highest amount of penetrability, being able to penetrate even lead. On the other hand, my brother told me that super low frequency radio waves are used to communicate ...
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53 views

Do two waves of different frequencies create a resultant wave of lower frequency?

In my results for testing background noise, i found that while strumming a guitar in: a noisy area, the frequency picked up by the mic was 352 Hz while in a quiet area, the frequency picked up by ...
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43 views

Why array of telescope is used?

To increase the resolution of an instrument, smaller wavelength and larger aperture is desirable. It is mentioned in some textbooks that the "effective" diameter of a telescope can be increased by ...
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234 views

Light wave crossing media and the relationship between speed, wavelength, and frequency

There are many threads on this topic (like this one) but one aspect about the equation $ v = \lambda\nu $ still confuses me. I have read that frequency does not change when light crosses into ...
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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 ...
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545 views

Standing wave velocity

My question is simple: How is it that a standing wave has velocity? I mean, it's not travelling... A lot of equations depend on this concept, for example: $f_n = \frac{nv}{2L}$ Here we're ...
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1answer
87 views

polarization of a transverse wave travelling in ionosphere with polarization direction perpendicular to earths magnetic field

Assume a transverse electromagnetic wave entering ionosphere such that its Electric field of wave is perpendicular to earths magnetic field. Now, i read that as it will enter plasma, the wave will ...
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24 views

How does temperature affect the frequency produced by a fixed vibrating string

How does temperature affect frequency produced by a fixed vibrating string? In the case of the sonometer experiment, the length is fixed so temperature cant really affect length. It affects the ...
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Interference of two waves of different frequencies relevance to background noise + sonometer

If two sound waves of different frequencies are recorded then does the interference between the two waves of different frequencies alter the resultant frequency recorded. In better context, I'm ...
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14 views

Question about dark fringe in diffraction

In finding the angle for the mth dark fringe of single slit diffraction using Huygen's principle, they usually split the slit into equal portions. For example, to find the first dark fringe the slit ...
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1answer
32 views

Does the term phase difference apply only for sinusoidal waves?

This question may sound dumb, (it will to me, hopefully, in a day or two!), but does the term phase difference apply only for sinusoidal waves? Wikipedia defines 'phase' as the following: Phase ...
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25 views

Energy conservation in interference?

Does interference of light follows first law of thermodynamics? If yes then where does light vanishes in minimum interference pattern?
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Why and how is sound produced when two objects hit each other?

When two objects collide and undergo a partially inelastic collision (so every one we experience in every-day life), they rebound to a certain degree, but kinetic energy is not conserved. Thus, the ...
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3answers
102 views

Does sound have a “louder” direction?

I have a question about the propagation of sound waves. We have two TV's in our house that are almost right on top of each other. One is located on the first floor and the other one is located on ...
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1answer
106 views

What does a light wave look like (3d model)

What does a light wave look like? The only models I can seem to find online are 2D waves, they just look like sin() graphs. I have seen the models of the two components of "light waves" (electric ...
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Can we measure the depth of water by scattering water?

Suppose we release an object and make it fall on the surface of water, then the scatter of water is recorded, Taking some observations, can we calculate the depth of the water by analyzing the ...
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33 views

modelling the sound wave of a guitar string with an equation [duplicate]

Currently I'm doing a physics related coursework on guitar strings and wave. I would like to ask how I can model the sound wave of a guitar with an equation. I asked some of my teachers and they told ...
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Pouring oil on choppy water to calm it , does it work and if so how?

Near where I live, local fishermen often bring cans of castor oil with them, to calm the water around their boats, if they feel bad weather is due. They claim this method of sea calming works, ...
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4answers
68 views

Why do not the ripples on a pond form a 3 dimensional wave?

I can see that that the expansion of the the circles happens in a two dimensional plane. Therefore, we say that a two dimensional wave is formed. But, why cannot we count the vertical disturbance so ...
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1answer
43 views

How does one measure the phase of a wave?

Given an electromagnetic wave of unknown characteristics, is it possible to measure its phase? Or does it always have to be inferred from interference with another wave (e.g. beating etc.)?
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111 views

Path Difference Due to Angled Incident Light

If light incident on a diffraction grating makes an angle $\alpha$ with respect to the normal to the grating, show how $$m \lambda = d\sin\theta$$ becomes $$m\lambda = d[\sin(\theta - \alpha) + ...
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15 views

Waves ionsphere?

Explain why the ionosphere can be treated as a plane mirror when transmitting short-wave radio, even though it is a curved surface. Is it because the area involved is small?
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Find the diameter of the tube and frequency of resonance [closed]

A tube of a certain diameter and of length 48 cm is open at both ends. Its fundamental frequency of resonance is found to be 320 Hz. The velocity of sound in air is 320 m/sec. Estimate the diameter of ...
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What do light wave oscillations look like?

High school physics student here, so please bear with me for a moment. I know that light waves oscillate, but I don't know how. In textbooks and diagrams they're portrayed as wavy lines traveling ...
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143 views

Why is the wave equation so pervasive?

The homogenous wave equation can be expressed in covariant form as $$ \Box^2 \varphi = 0 $$ where $\Box^2$ is the D'Alembert operator and $\varphi$ is some physical field. The acoustic wave ...
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24 views

Determine beat frequency

I am currently trying to create a plot of the beat from superimposing two sine waves. I know the formula is given by $$\sin(\omega_1 t)+\sin(\omega_2 ...
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15 views

Determining the offset from a wave [closed]

From the figure below, determine the offset from the break-even point: (a) 1.0 m from the origin ; (b) 1.5 m from the origin ; (c) 2.0 m from the origin . Give your answers in meters, with a ...
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determining the speed of the wave by a picture [closed]

The figures below show the displacement versus time for two particles in a medium within which to observe the propagation of a pulse. From these figures, determine the speed of the wave. Could you ...
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Young's modulus of one material [closed]

You hit the end of a 1.5 length of metal bar me simultaneously triggers an electronic timer which is automatically stopped as soon as a microphone located at the other end of the bar, detects sound. ...
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How do we know that the CMBR is the oldest light?

How do we know that the CMBR is the oldest light which we can see? Is it based just on the facts 1.that waves redshift with expanding space, and 2.predictions of the big bang theory; Or is there a way ...
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Is it possible to use “negative sound waves” to “cancel out” a sound to create silence?

I saw youtube videos that claimed to do this, although I'm quite certain the videos just excluded sound and lied. However, I am wondering if the physics of this is actually possible - to create a ...
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1answer
25 views

Power of a wave in a string

My text of physics, Gettys', shows how the energy, both kinetic and potential, of a small element $\Delta x$ of a string, through which a wave (whose wave function is $y:\mathbb{R}^2\to\mathbb{R}$, ...
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31 views

Wavefront explain [closed]

I know that asking this question is a little weird, but I cannot understand the wavefront after searching a lot of material online. Does a progressive wave have an infinite set of wavefronts? Why ...
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1answer
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Conventionally, how many amplitudes does a (harmonic) oscillator pass through in one full cycle? [closed]

I don't know the typical scientific convention. My book says there are 4 amplitude. But no matter where I start the oscillator , the answer is at most 3.
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A heavy rope is attached to one end of a lightweight rope [closed]

If one end of a heavy rope is attached to one end of a lightweight rope, a wave can move from the heavy rope into the lighter one. (a) What happens to the speed of the wave? (b) What ...
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1answer
26 views

What is the Optimal Separation Length for the Tines of a Tuning Fork?

I'm building tuning forks (for fun... why not?), and among one of the design decisions is how far apart should I place the tines (the two long prongs) from each other. I'm not entirely certain whether ...
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1answer
39 views

How large or small can frequency in the EM spectrum get?

The largest frequency range is gamma rays, but does the EM spectrum 'stop' somewhere? Like is there a limit to how large a frequency can get? Or how small frequency can get? Is it one of those things ...
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1answer
29 views

What really is the significance of the resonant frequency in terms of “ease of vibration”?

I was studying the concept of resonant frequency and I've read quite a few articles and notes on it. What I have understood from what I have read is that the resonance frequency of an object is its ...
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2answers
91 views

Why does a continuous water stream form ripples when colliding with a surface?

I was in the shower one day washing my hair, and noticed that the water falling off my hair formed perfect streams that ceased to break into droplets for quiet some distance (probably about 5-6 cm). ...
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71 views

Physical meaning of wavelength of an EM wave

What is the physical meaning of the wavelength of light? This question has been asked before but I cannot find a satisfactory answer. Some respondents have said that the question is vague, I don't ...
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1answer
35 views

Differentiating between standing waves (stationary waves) and progressive waves [closed]

The question is ''Differentiate between standing waves (stationary waves) and progressive waves?" I do not understand what exactly they would like to hear. Should we talk about the frequency, ...
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3answers
39 views

How to derive the formula for phase difference $\Delta \Phi = \frac{2\pi}{\lambda}\Delta x$?

How can I derive the formula $$\Delta \Phi = \frac{2\pi}{\lambda}\Delta x$$ for calculating the phase difference? On a relative note, why does the particle velocity have an upwards direction when ...
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1answer
182 views

How does a longer wavelength penetrate deeper with Rayleigh waves?

I'm struggling slightly to understand this idea. I've slowly been building up an explanation, so at this stage it might be just some confirmation I'm looking for, but also some guidance if I'm off ...
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42 views

Amplitude of wave with distance

How is the amplitude related to distance with waves on a plane? I am creating a mathematical model for water waves in a ripple tank, first assuming that there are no other factors that may affect the ...
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Wave propagation in micro strip waveguide

I am trying to understand wave propagation in micro-strip waveguide, the way i came to understand rectangular waveguide is this way (in brief): EM waves can be understood as reflecting from the ...