Questions tagged [resonance]

Resonance is a characteristic of physical systems having a structure that allows energy to flow between various states at a specific, oscillatory rate (resonant frequency). For a stable resonant system at steady state the internal energy is either fixed without losses or the rate of energy input is equal to the energy losses.

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How is Mössbauer spectroscopy so resistant to thermal motion?

Mössbauer spectroscopy detects tiny shifts (on the order of $\rm{\mu eV}$ or $\rm{meV}$) in a gamma ray's energy due to the chemical environment of the nucleus. The scan consists of moving a source ...
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Driven Pendulum

If the point of suspension of a pendulum is driven periodically in the vertical direction , we can derive the equation of motion for the suspended mass to be of the form, $\ddot{\theta}(t) + (a-b\cos{...
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How do I calculate the resonance frequency of a block of material?

I would like to know how I go about calculating the resonance frequency for an object, given its material properties and dimensions. For example, a small rectangle $X$ by $Y$ by $Z$ dimensions, I ...
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Why do scattered waves vanish when the wavenumber of the incident wave is an eigenvalue of the interior Dirichlet problem. Where has the energy gone?

I normally work with numerical computations for wave scattering, but I am now trying get a better understanding of the physical processes underlying the theory, in particular what happens to the ...
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Why would oscillation of a gas column inhibit rather than promote mixing?

Many years ago I helped to support an experiment conducted in Japan which investigated the effects of high frequency oscillation ventilation (HFOV) on the mixing and distribution of gas into the lungs....
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What is the mechanism of subharmonic oscillations?

It's clear to me from linear systems theory that energy manifested within a fundamental mode of resonance can saturate with the excess energy spilling over into harmonic frequencies greater than the ...
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Metastable bound state in resonance scattering

In resonance scattering, why does the mean lifetime of the "metastable" bound state depend inversely on the width of the resonance?
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Chladni Plate Mathematics

I am a high school student doing an IB Extended Essay investigation concerning the resonant frequencies of Chladni plates of differing materials and sizes. Would someone please explain the definition ...
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Does putting a part under stress change its natural frequency?

It is easy to imagine how tension changes the natural frequency of a wire. Intuitively it happens with a guitar string when you bend the neck. However, does putting a beam under stress (internal or ...
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How is “linewidth” defined for a damped driven oscillator?

Suppose we have a damped driven harmonic oscillator governed by the following equation of motion: $$\ddot \phi(t) + 2 \beta \dot \phi(t) + \omega_0^2 \phi(t) = J(t) \, .$$ In the case that $J(t) = A \...
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What are the conditions for molecular,photon resonance other than same frequency?

I know that the basic condition for molecular,photon resonance is same frequency but what are the other condition for this process like phase relationship,round trip of the molecules and so.Also can ...
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Standing spherical wave solution

Let's say we have a spherically symmetric light wave $u(r,t,\theta,\phi)= u(r,t)$ that satisfies the following wave equation with spherically symmetric potential $V(r)=2/r^2$ (also set $c= 1$ so $\...
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How does a “Haskell Resonator” work?

I would like a simple explanation of how a "Haskell Resonator" works. You may assume that I understand the Wikipedia paragraphs on open and closed resonator cylinders. Exactly how does placement of ...
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Bound state of $\mu^- \mu^+$ . Why non-relativistic muon states?

Peskin & Schroeber page 148 discuss the creation of a $ \mu^+ \mu^-$ resonance state . Equation (5.44) describes the creation of a Spin Up bound $ \mu^+ \mu^-$: $$ \mathcal{M} = \sqrt{2M} \int \...
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Is there a resonance within the earth, separate from the Schuman resonance?

In a very recent biography of Nikola Tesla by Bernard Carlson, the author explains that Tesla measured the resonant frequency of the earth using his invention - the amplifying transmitter. Tesla came ...
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Resonance condition in confocal cavity

In a confocal cavity, a beam traverses the length of the resonator 4 times between two transmissions along the same ray. . For example, in the above figure, path difference between two beams that ...
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Reflector Klystron and Isolator for ESR/EPR Experiment

I am doing a lab on ESR/EPR, and I would like to know how the reflector klystron operates. It is very old and the company who made our model does not exist anymore and there are no operation manuals. ...
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Is there an equation that tells you more about the amplitude of an object which is in resonance?

I'm a high school senior and I have to write a paper about resonance and differential equations. I've been searching the Internet for a long time, but I haven't found an equation that is properly ...
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Resonance and energy flow

In this post, Alfred Centauri describes the resonance as a phenomenon which appears when 'the energy flow from the driving source is unidirectional' and then shows that this is the case for $\Omega=\...
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Faraday waves and Chladni plates

I am a High school student who's writing a research paper about Faraday waves and Chladni plates. I've been doing a lot of research on Faraday waves specifically, as there aren't many sources that can ...
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Chladni Patterns (Length Factor)

I've recently been conducting experiments on the Chladni Plates, testing out how the length of a square Chladni plate (and consequently its area) affects the frequency at which each respective chladni ...
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What is the mathematical basis behind using a chirp signal to determine the resonant frequency of a second order differential system?

It is a common practise for engineers to try to determine the resonant frequency of a system through a chirp signal. Given a damped oscillating system with displacement $x$, driven by a chirp signal ...
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How is sound produced in pea whistles? (I think they're called police whistles in the US.)

I read the topic called 'Whistle Physics' on this forum. From what I gathered there, @alephzero seemed to be saying that changes in air pressure cause air to be alternately sucked in and pushed out of ...
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Air flow through a penny whistle

I am confused about exactly how air flows through a penny whistle. I would also like to double check that I understand correctly what the cavity of resonance is. Say I have a whistle like this: <...
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Measuring time in the photoelectric effect

Consider the following hypothetical: An atom is traveling with a velocity of v to the left, directly towards an incoming photon, as crudely depicted below. p----> <----A Question (1): What is ...
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What 2d shapes would have the most resonant frequencies?

A square Chladni plate has a handful of resonant frequencies in the audio range. If you wanted to make a plate with very many (infinite?) resonant frequencies, what shape would be best? You wouldn't ...
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Model for sound generated by air flowing through pipe

I'm trying to write a program simulating the sound of an petrol car engine, just for fun. As a part of this, I'm trying to model the sound of air escaping the combustion chamber through an open ...
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overstability vs resonance: what is the difference?

Reading about discs, I encountered the word 'overstability' that its difference with resonance is not clear to me. Does anyone know the difference?
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Aerogel resonator

I'd like to find an approximate relationship between the peak velocity for an aerogel resonator, resonating at (angular) frequency $\omega$, and the amplitude of motion. Essentially the fact it's ...
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What is the effect of a pair of different sounds or frequencies upon an object?

I am new to learning about the physics of sound, resonance, resonant frequency, and standing waves. Most of the sources I am reading describe the effect of a single frequency on an object when that ...
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Modeling the field inside a cavity resonator

As part of the design of an experiment, I am trying to model the magnetic fields inside a hollow rectangular waveguide cavity. I have not had any problems calculating the cavity physical dimensions ...
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How to modify Breit-Wigner resonance formula in case of a nearby threshold?

When calculating the scattering cross-section via the resonance with mass $M$ one can use the Breit-Wigner formula \begin{equation}\frac{1}{s-M^2+iM\Gamma},\end{equation} where $\Gamma$ is the ...
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Why does scratching a blackboard gives such a painful noise?

I think we all have heard that terrible sound coming from scratching a blackboard with your nails. How is it produced? Has it something to do with the length of our nails?
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What is Lamè mode?

I am trying to read some of the articles that says Lamè mode. But I can't find in google that describes Lamè mode. Can anyone quote good reference for this term?
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LCR circuit at resonance

I am studying about the LCR circuit and have a question regarding potential difference across inductor and capacitor. From the thing I have studied I came to know about that potential across inductor ...
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Optical Delay Lines

Why does the peak group delay for an add-drop ring resonator's drop port reduces to 1/4th of that of an all-pass ring resonator? Shouldn't it just be half of its value as the transit length is ...
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On resonance of an RLC circuit

How do I prove that the width of resonance in an RLC circuit is the inverse of the proper time of the circuit? I know that the amplitude of charge in the condensator is $$Q(\omega)=\frac{V_\text{max}/...
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Off resonance operation of tightly coupled coils for maximum efficiency?

On Wireless Power Consortium webpage there is an article about Magnetic Resonance. These paragraphs in the page surprised me: You might expect that operating tightly coupled coils at resonance ...
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Exploiting Resonance to Make a Bound State with Gamma Rays (and other Very High Energy Particles)

One obvious consequence of any finite potential is that a high enough energy wave-function will not form a bound state, either they are high enough energy they will generally just bypass the barrier ...
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Why the current through a resonant tunnel diode drops when the bound state goes below the conduction band?

The IV curve of a resonant tunneling diode is N-shaped. The rise in current flow happens because the bound state (the energy state in the well) enters the thermal area of the conductor ($\mu_1 + ...
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Earth connection through resonant inductive coupling with Schumann resonances possible?

I have been playing around with Tesla coils for a while now, but one limiting factor for portability is the fact that it requires an earth connection on the secondary coil. Since a Tesla coil works ...
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Can a $TEM_{00}$ beam incident on a confocal cavity along its optical axis excite modes other than $TEM_{00}$ in the cavity?

Can a $TEM_{00}$ beam incident on a confocal cavity along its optical axis excite modes other than $TEM_{00}$ in the cavity? If not, is the FSR of the confocal cavity $\frac{c}{2L}$ in this case, ...
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What is the magnitude of the sound that a Helmholtz Resonator attenuates?

I know that the shape of the Helmholtz Resonator, specifically its neck shape and the volume of its cavity, determine the resonance frequency of the resonator. Moreover, the resonance frequency is ...
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Resources on Physical Baryon States as mixings of multiplet states

I've been told, and have seen in papers (search for "mixing") that baryon resonances are not plucked from pure group theoretic multiplets, but are most often found to be mixings of states in different ...
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Resonant Hamiltonian Mechanics

My question is regarding applying averaging theory to a perturbed Hamiltonian. Now, my Hamiltonian is of the form $$H=H_0 + R(q_i,p_i)$$ Where R is the disturbing potential which is a function of the ...
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Harmonic Oscillator (2DOF) - Do these results seem correct?

I solved a 2DOF system for a buried harmonic oscillator with a forcing function, but I'm not sure what I should be seeing in terms of resonant frequency shift & velocity. The resonant frequency of ...
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What does a negative end correction mean?

I was asked this question in one of my tests: "In an experiment to measure speed of sound by a resonating column a tuning fork of frequency 500 Hz is used. The length of air in the column is varied ...
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Loudspeaker attached to cylinder - effect on speaker SPL?

I have a loudspeaker that is facing into a long cylindrical piece of PVC pipe of length $L$. The loudspeaker is sealed in so that no air can escape around the edges. The pipe is open at the other end. ...
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Negative surface plasmon decay rate

I'm calculating surface plasmon decay rate $\gamma $ as [1], $\gamma = \eta \epsilon''$ where, $\eta = (d \epsilon_{g}'(\omega)/d \omega)^{-1}|\omega = \omega_{at\:resonace}$ and dielectric ...
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Superposition of normal modes, frequency or time domain?

Very basic question about a complicated topic. I want to know the field scattered by a sphere. In the book Absorption and Scattering of Light by Small Particles by Bohren & Huffman, they arrive ...