Questions tagged [harmonics]

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Is this image on harmonics and overtones wrong?

I saw this image and believed this to be the definition of what the relationship between harmonics and overtones to be in strings, closed pipes and open pipes. That the $n^{th}$ harmonic = $n-1^{th}$ ...
John Hon's user avatar
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How was the $\Gamma _\mu$ be used as a gauge condition in the Generalized Harmonic formulation $R_{\mu\nu}$

I'm watching a video(ICTP-SAIFR Numerical Relativity by Sascha Husa) where he mentioned that $$R_{\mu\nu} =-\frac{1}{2} g^{\lambda \rho} g_{\mu\nu,\lambda \rho} +\nabla_{ (\mu }\Gamma_{\nu)} +\...
ShoutOutAndCalculate's user avatar
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How is a resonant bandpass filter similar/different from a damped mass-spring oscillator? They seem to behave both similar and different in testing

Background I am using resonant bandpass filters as musical oscillators. One can excite an array of them at harmonic frequencies and given Q values for a note by, for example, running a burst of noise ...
mike's user avatar
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String vibration dimensions

We're all familiar with the typical diagrams of standing waves of a string, as in this image from Wikipedia: The thing that bothers me is that they ignore the reality that the string is vibrating in ...
Eric Singer's user avatar
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Observations of harmonics in gravitational wave experiments

In gravitational wave astronomy, we usually observe $f_{GW}=2f_K$ (gravitational wave frequency twice the orbital frequency from keplerian motion). However, we also know there should be harmonics with ...
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Change in Frequency while Tearing Paper

Let us assume you have a 30cm strip of paper, and you tear it lengthwise. Let us abbreviate the frequency produced when you reach the end of the paper as $f_2$ and the frequency of sound heard when ...
Schrödinger's Cat's user avatar
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Air Columns non-resonant frequencies

I understand that both open and closed-end air columns have many resonant frequencies, called harmonics and a fundamental frequency. At these frequencies, we expect to observe standing waves of ...
Sonite's user avatar
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Loss of energy during harmonic resonance

I have been trying to determine the function describing how energy is lost during harmonic resonance: Say an input of energy at the resonant frequency of a closed resonator. I know the following ...
Will Chatfield-Taylor's user avatar
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How does a string thickness affect the frequency of its harmonics?

The harmonics of a theoretically infinitely small diameter string are pure integer multiples of the fundamental frequency. However, a real string has a thickness, and when vibrating in a harmonic, the ...
Don Rechtman's user avatar
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Natural Harmonics on a String

Consider the Dirichlet boundary value problem of a guitar string stretched between two fixed points which is made to oscillate by pinching and releasing the string. It can be shown in quite ...
Tom's user avatar
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Viewing String Oscillations with a Camera

In this video, a demonstrator shows normal modes on a string. If one is doing this with a high speed camera, how many frames per second does one need to view the oscillations? My intuition was that ...
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What is heard when a tuning fork is struck?

When a tuning fork is struck I hear two tones. From a distance I can hear a high octave frequency of the pitch of the tuning fork. Though, if I listen to it closely (closer to my ears), I also hear a ...
Lecifer's user avatar
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Why is the energy of the harmonics in a vibrating string not infinitesimal?

When you pluck a guitar string, initially the vibration is chaotic and complex, but the components of the vibration that aren't eigenmodes die out over time due destructive interference. This ...
silver's user avatar
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Phase difference of standing waves

The phase difference of a standing wave is zero. The above statement is found online when searching about standing waves. However, it doesn't make much sense to me. Consider the above diagram of a ...
Jeremy Clarkson's user avatar
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Harmonics in closed and open pipes

What exactly would happen if we sent a frequency that was not one of the harmonics into a closed and open pipe? What would happen if we gradually increased this frequency? From my understanding, I ...
Jeremy Clarkson's user avatar
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Phase difference problem

What's the phase difference between A and B on the following diagram. Where it is a standing wave. This question doesn't even make sense to me as from watching animations of standing waves, points A ...
Jeremy Clarkson's user avatar
2 votes
2 answers
164 views

Clarifications on standing waves within a pipe?

Standing waves are causing great confusion for me. I have read many answers on stackexchange. However, I still don't understand standing waves within closed and open tubes. Problem 1. I struggle to ...
Quin Gardiner Bax's user avatar
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1 answer
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How is wavelength defined for standing waves?

How is wavelength defined for standing waves? I cannot understand why the first harmonic is half a wavelength rather than a full wavelength. I see how wavelength is defined for progressive waves but I ...
Quin Gardiner Bax's user avatar
3 votes
2 answers
206 views

Why do water sounds different at different levels?

I observed that when we fill a water bottle it sounds different at different levels of height. means it sounds different while filling at $\frac{1}4$ level and different at $\frac{1}2$. I just want to ...
kl kick's user avatar
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How to create a standing wave that doesn't oscillate with the fundamental frequency?

Is there a way to make the string on my violin vibrate in an overtone frequency instead of the fundamental frequency?
This is Mark's user avatar
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First Harmonic/Closed Tube/Net Transfer of Energy

Standing waves have no net transfer of energy. But, when watching simulations of the first harmonic for a closed tube, I see what looks like a transfer of energy - the particles clearly appear to ...
Vinny's user avatar
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Can a pendulum have detectable harmonic frequencies

Can a pendulum produce harmonic frequencies? Like could I detect harmonic frequencies if I had a sensor on the pendulum?
v_ecila's user avatar
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Why is time harmonic follow the form of $e^{-i\omega t}$, not $e^{i\omega t}$? [closed]

In physics, when we solve an PDE or ODE, the solution usually has the form of \begin{equation} f=C_+e^{i\lambda x}+C_-e^{-i\lambda x} \end{equation} and the "causility" will eliminate one ...
Tippsie's user avatar
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7 votes
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What do I hear when listening to a computer-generated sine wave?

When I use a sine-wave generator (such as this one), I give credit to the software and my hardware that a pure sine wave is produced (as close as is technologically possible) — that is, no harmonics. ...
Aaron's user avatar
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In what respect does the wave pattern of a noise and music differ?

Does the wave pattern of musical sounds contain only harmonics (other than the fundamental frequency) while noise contains random overtones (that are not harmonics)?
Golden_Hawk's user avatar
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The definition of "total curvature" for a scalar field

In Modern Electrodynamics, Zangwill remarks that the total curvature vanishes at every point where $\nabla^2 \varphi = 0$. Now my question(s): how is "total curvature" defined for a scalar ...
EE18's user avatar
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What is the simplest PDE/ODE/model I can use to understand how nonlinearities can lead to leakage of energy to higher harmonics in an oscillator?

I came across this problem in the study of surface waves in an oscillating cylindrical vessel of liquid. There are various eigenmodes described using Bessel functions, and energy transfer can happen ...
Chillpadde's user avatar
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Is there a 'better' tuning frequency than 440 Hz? [closed]

My apologize if this question is a bit broad or open ended but I'm asking here rather than a music forum for two reasons: I'm trying to gain a better understanding of the physics of sound and ...
Bailen Huggins's user avatar
2 votes
2 answers
1k views

What are harmonic waves?

I am studying waves for my examination. Harmonic waves is also in my syllabus and I don't know what it is. I searched for it on google and got two possibly different answers. One answer is from en....
user12137152's user avatar
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HOW are harmonics generated in longitudinal waves on the particle level?

I have been looking through the physics.se and all over the internet for weeks now honestly, and I still don't understand how harmonics are formatted on the particle level. Yes, I know that only ...
Dimitri's user avatar
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The cause of higher harmonics amplitude drop in an air column?

In the case of the real life string, I believe I understand the cause of the amplitude drop as we go into higher harmonics: the bendability of the string is not infinite and as we get lower ...
Dimitri's user avatar
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Length of a water column executing SHM in a U-shaped Tube

I was watching the lecture 30 of Walter Lewin ( 8.01 ). Here is a link: https://youtu.be/hAYeA3Wwb4U At 29:30, when he was describing the SHM of water in a U shaped tube. Lewin says that for the ...
Ralf's user avatar
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4 votes
1 answer
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Does rope in a standing wave expand and contract as it moves between being straight vs sine?

Images of standing waves often show two people using a jump rope. The shape of the rope goes from straight to waves to straight, then a sine wave the other way and then straight again as it repeats. ...
peawormsworth's user avatar
2 votes
1 answer
82 views

Why only harmonics allowed in the Casimir effect?

My question is really a request for an intuitive explanation as to why only harmonic frequencies of photons allowed between two conduction plates. Why do the plates have to be conductive? And can real ...
Nazuid's user avatar
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2 votes
2 answers
186 views

Is timbre a physical noumenon or a perceptual phenomenon? [closed]

I have a question relating the "timbre" of a sound, namely what is exactly and exhaustively defined by this word? Most definitions that I come across seem somewhat loose as "the color ...
Dimitri's user avatar
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1 vote
3 answers
450 views

How can I calculate the number of nodes on a plucked string?

Given the length of the guitar string, can you predict the number of nodes that would exist on that string? My textbook says that there are an infinite number of harmonics that can be created when a ...
Salah Daoud's user avatar
1 vote
2 answers
158 views

How does one apply the phase change of $π$ on reflection at the rigid end of a string?

Consider a string, with a free end $P$ and another end $Q$ which is rigidly fixed. Now, we start oscillating the point $P$ (with $0$ initial phase difference) and a wave starts traveling(in the ...
user avatar
2 votes
4 answers
138 views

Does the standing wave equation proof require $\ell=Nλ$? [closed]

Consider two identical sources $S_1$ and $S_2$ of waves, separated by a distance $\ell$ (as shown in the figure). The sources produce waves in opposite directions(and towards each other). Now, ...
user avatar
2 votes
2 answers
985 views

Why does an antinode form at the open end of an organ pipe?

I recently learnt about reflection of waves in various media and the resultant standing waves formed. In a string which is tied at an end, the wave formed reflects with a phase difference of 180 (at ...
user avatar
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1 answer
60 views

How to calculate the overall harmonics of a system of tubes?

Let's say there is a tube closed at one and and open from the other. The open end is connected to another tube (of smaller diameter) which is open from both ends. How can I calculate the overall ...
Ashar's user avatar
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2 votes
2 answers
200 views

What exactly happens, step by step, in string harmonics?

I know that a string when plucked shows harmonics but I do not really understand how. Like, I understand resonating air column and how standing waves are formed there, but I can't seem to get the step ...
AltercatingCurrent's user avatar
6 votes
2 answers
449 views

Why does plucking a string produce harmonics instead of a pulse?

If I jerk a wire from the free end fixed at an end and then fix the free end, it will produce a pulse travelling back and forth between the two ends. So in a string fixed at both ends, if we pluck it ...
AltercatingCurrent's user avatar
0 votes
1 answer
64 views

Why is the Ocean Blue? [closed]

I'm writing an article on the physical property that binds Music and Water -- Harmonics. I understand that the blueness of ocean water is due to the three vibrational modes of water (i.e, symmetric, ...
rb3652's user avatar
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1 vote
1 answer
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Standing wave in a string clamped at one end

*In the case of a standing wave formed with one end clamped (fixed), there is an anti-node at the free end irrespective of the overtone. My question is why is there has to be an antinode. Is there any ...
Devraj bahl's user avatar
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Steven Weinberg says $L$ is the fundamental EM wavelength in a cubical cavity $L^3;$ not the typically asserted $2L.$

This is from Steven Weinberg's Lectures on Quantum Mechanics, 2nd Ed., page 2: For instance, for a cubical box of width $L,$ whatever boundary condition is satisfied on one face of the box must be ...
Steven Thomas Hatton's user avatar
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Standing waves confusion

Its just so confusing as to why the antinodes are formed from the constructive interference by superposition of the wave formed by the incident wave and the reflected wave... The phase difference is ...
Ashiq Ibrahim's user avatar
2 votes
1 answer
69 views

Which harmonic we hear from organic pipe from all possible outcome?

I have gone through about each case of standing wave in open and closed organ pipe and understand antinode and node concepts. But i am confused that if all harmonics are possible in organ pipe, then ...
Sagar Rawal's user avatar
1 vote
3 answers
214 views

Plucked string eigenvalues/harmonic frequencies: integer multiples (or not)

I'm trying to derive a model of a plucked string from Newton's second law. My derivation results in $$ω_n = C\cdot\sqrt{n},\, n=1,2,3\dots\text{integer}$$ I think it should be $$ω_n = C\cdot n,\, n=1,...
Nick Boshaft's user avatar
1 vote
2 answers
727 views

Why are there both antinodes at both ends of the tube? [duplicate]

I learned stationary/standing waves the other day. For stationary waves in open tubes, the textbook says both ends must have an antinode. Can anyone tell me why? (shown as figure) And also, when ...
Bruce M's user avatar
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Upper limit of Schumann resonance harmonics?

This is a re-post from the Earth Science Stack Exchange which was posted two month ago. Due to the nature of the question and the SE site, it might be better to post this question here. As the Earth'...
C-Consciousness's user avatar