Resonance is driving a vibrating system to oscillate with greater amplitude at a specific preferential ("resonant") frequency, at which the system absorbs vibrational energy most efficiently.

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Sound waves - physics [on hold]

A closed organ pipe of length L is in resonance with tuning fork. If a hole is made at a distance L/4 from the closed end will there be resonance again? If so when?
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230 views

Why does amplitude of a mechanical wave increase and then decrease with increasing driving frequency?

I was doing an experiment where I explore how the frequency of the oscillation of a vibrating water hose (the end of the water hose), affects the amplitude created by the water path (a wave-like ...
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111 views

Capacitor/Inductor Resonance

I am struggling to understand the concept on resonance in electric circuits. I understand that a inductor builds up a charge on it, then the current flows to the capacitor, charging it. But then ...
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19 views

Does resonator will always dampen the driving oscillator?

I was doing a question about resonance of sound box connecting to a tuning fork. It asks why the sound lasts for a shorter time with sound box than if the tuning fork is struck identically without the ...
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37 views

Vibrations of a string [closed]

A string with length $L$ is stretched between two fixed points. The string can't vibrate with which wavelength? Four options are given, namely $L$, $L/2$ , $2L$ and $4L$. I know that the ...
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Mechanism behind “Hoot Tube” demonstration

For years I've been puzzled by how the "Hoot Tube" demonstration shown at the end of this video (around 2 min 45 sec) actually works. I've done the demo myself with a double walled stovepipe from the ...
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58 views

Finding resonant amplitude [closed]

For a system of oscillations described by the differential equation: $$ \cfrac{d^2x}{dt^2} -\epsilon \cfrac{dx}{dt} + x = \cos(\omega t)$$ We find that the response amplitude $R(\omega)$ to be: ...
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270 views

Can friction change the resonance frequency of a system?

I am simulating the transient response of a mass-spring-damping system with friction. The excitation is given in the form of a base acceleration. What I am not sure about is: can the friction change ...
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419 views

Resonate frequency of an object?

Below is a paragraph taken from the web site, physicsclassroom.com: It is often useful to think of these electrons as being attached to the atoms by springs. The electrons and their attached ...
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17 views

What is/are the resonant frequencies of a closed liquid cylndrical jar

My general question is how to calculate (via a formula) the resonant frequency of a cylindrical jar containing a liquid, assuming the speed of sound of that liquid is known and the solid material If ...
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146 views

Does spatial coupling prohibit resonances due to an external source field?

The harmonic oscillator coupled to a sinodial external source $$\frac{\partial^2 x(t)}{\partial t^2}+\omega_0^2 x(t)=F_0\sin(\omega_\text{ext}\ t),$$ has the solution $$x(t)=x(0)\cos(\omega_0 t)+C \...
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339 views

Singing: Resonance body open-closed or closed-closed?

Googling yields contradictory results, so here my question: When I sing, my vocal chords vibrate, but my whole body is the resonance body, right? So I would say that when I think about standing waves ...
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78 views

How to derive end-correction value relationship for open-ended air columns?

According to Young and Freedman's Physics textbook, in open-ended air columns like some woodwind instruments, the position of the displacement antinode extends a tiny amount beyond the end of the ...
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64 views

How can I prove that antinodes are present at both open ends of organ pipe mathematically?

I know that for anti node to be formed the magnitude of displacement should be maximum at there. For standing waves in an organ pipe, the boundary conditions are such that anti nodes are formed at ...
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63 views

Resonant Frequency of 2 mass spring system

So the question goes if I has a spring with spring constant $k$ and two masses attached to this spring (one on either side) what is the resonant frequency of the system in terms of $m$ and $k$? ...
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366 views

The demise of the Tacoma Narrows bridge was casused by aeroelastic flutter. But isn't that just a special case of resonance?

Much of the research I've done on the Tacoma Narrows bridge disaster of 1940 attribute the collapse of the bridge due to aeroelastic flutter - not strucural resonance. But isn't aeroelastic flutter ...
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31 views

The derivation of how resonant frequency can amplify vibration in bridge

refer to here: One of the most famous examples of a resonance disaster is the 1940 Tacoma Narrows Bridge collapse in Washington, USA. This came about not simply as a result of mechanical ...
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23 views

Mathieu equation nonstable solutions

This israther mathematical question, but it is connected with some physics. Let's have Mathieu equation: $$ \tag 1 y''(t)+ (a -2q\cos(2t))y(t) = 0 $$ Suppose domain of parameters $a, q$ values, where $...
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287 views

Why does the length of a wind instrument affect it's pitch?

I understand how length of a string on any string instrument affects it's pitch, but I don't understand how a short wind instrument produces a high pitch.
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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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The effect of secondary orientation on resonant voltage

Imagine a circuit with an inductor coil (Coil 1), in series with a capacitor, connected to a function generator. Now, a secondary circuit, constructed with an other inductor coil (Coil 2), connected ...
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1k views

Why does a container with fluid make different sounds at different fluid levels?

Have you ever noticed that when you are filling a container with fluid. As it approaches the top, it makes a different sound? You can tell by listening when your about to reach the top. Why is this?
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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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30 views

Capacitor and inductive coil in AC circuit

Does increase in $L$ of inductive coil with variable no. of turns or $C$ of capacitor with changeable capacitance increase frequency of the circuit?
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28 views

How does cavity resonance produce EM waves? [closed]

My understanding is it acts like a capacitor and inductor in a loop. The capacitor releases stored energy which is absorbed by the inductor through a magnetic field which then returns it to the ...
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Excitation of air with the eigen-frequency

I was just wondering (as a layman) what the eigenfrequency of breathable air is? If it exists: what would be the effects of exciting air with its eigenfrequency (w/ regard to humans, matter nearby?)
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Lorentzian nature of reflected microwave power in Electron Spin Resonance

Reflected microwave power has Lorentzian shape when plotted against frequency in ESR. How to mathematically prove this?
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33 views

gradient strength units in MRI

This may not be the appropriate forum for this but seemed to be the closest. I am trying to understand some concepts around MRI physics and it is common to use external magnetic fields created using ...
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How is Mössbauer spectroscopy so resistant to thermal motion?

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

Why the common beam in Barton's pendulum?

N So the theory is that R vibrates with largest amplitude due to resonance. Because when measured from the common beam its length is the same as that of A, so A's vibration would pass to R the same ...
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Is the length of the day increasing?

In Frontiers of Astronomy, Fred Hoyle advanced an idea from E.E.R.Holmberg that although the Earth's day was originally much shorter than it is now, and has lengthened owing to tidal friction, that ...
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Explanation of absorption from Bloch Equation

Suppose in a magnetic resonance experiment the microwave/rf field is applied in x-direction.How to say that the component of magnetization which is out of phase with the microwave magnetic field leads ...
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18k views

Does the human body have a resonant frequency? If so, how strong is it?

Inspired by this question on Music beta SE, I'm wondering if the human body has a strong resonant frequency. I guess the fact that it's largely a bag of jelly would add a lot of damping to the system, ...
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Why doesn't a transmission line mess up an antenna resonance?

I don't understand why the resonance of an antenna is not affected by the transmission line to the receiver. For example, given a dipole antenna like the following: The antenna length is carefully ...
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A conceptual doubt regarding Forced Oscillations and Resonance

While studying about the Resonance and Forced Oscillations, I came across a graph in my textbook that is given below:- Now, the author writes As the amount of damping increases, the peak shifts ...
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49 views

Amplitude of damped driven harmonic oscillator [closed]

I have a question that I can reason physically but mathematically I am not sure if my approach is correct. The amplitude of the oscillator is: $$A(\omega) = \frac{QF_{0}}{m}(\frac{1}{\omega_{0} \...
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131 views

Harmonics and the frequencies

Let's say we had a pipe which was closed on one side and open on the other. We can find the wavelength for the first harmonic. To find the second harmonic we just add one more antinode and find a new ...
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786 views

Why maximum energy transfer at natural frequency even if max amplitude occurs below $f_0$

This is a paragraph from my book: "For a damped system, the resonant frequency at which the amplitude is a maximum is lower than the natural frequency.However, maximum transfer of energy, or energy ...
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45 views

Sound pitch of glass with water

I have a glass (made from glass) at room temperature. I poured very hot tea in it and started stirring. No extra tea is poured in the glass. When hitting the glass with the spoon, I noticed the ...
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26 views

How can I get the Resonant Frequencies (Bode plot)? (Response of 2-DOF System)

I want to study the response of the system. I want to find the resonant frequency of the sprung mass (m1) and the resonant frequency of the unsprung mass (m2). Because I am not sure if I have ...
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75 views

What Magnitude(db) and Phase(deg) represent on Bode Diagram?

What Magnitude(db) and Phase(deg) represent on Bode Diagram? I am working on 2 DOF System and I want to understand some basic things. Below (on the picture) you can see the system, the transfer ...
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Role of Cavity Resonators in continuous wavelength-electron paramagnetic resonance(CW-EPR)

Why is it necessary to place the sample in a cavity resonator for obtaining EPR spectrum in CW-EPR? What role does a cavity resonator play in a CW-EPR spectrometer?
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56 views

Cavity resonator modelling and simulation of em fields inside the cavity

I want to model a cylindrical cavity resonator and study the different modes of em fields inside it using MATLAB/COMSOL. Please refer me books/articles or other resources so that I can achieve my goal....
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38 views

Swing: why does the body position modify the amplitude?

When a person swings, why does the amplitude of oscillations increase if the person changes the body position ? That is, when descending and approaching the vertical position, if the person extend his ...
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1answer
23 views

If there are two different standing waves of different lengths in an open air column, what frequency would resonate?

Suppose I am playing a hypothetical woodwind instrument with both ends open. Somewhere along the length of the tube is a hole, which cannot be at or near the exact center of the tube for the sake of ...
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32 views

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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1answer
88 views

Complex resonant frequency not resonant without imaginary part. So can I still just take real part as solution?

I am working with a matrix on a harmonic oscillator problem and the lowest (absolute) frequency $\omega_0$ where the matrix becomes singular is the resonant frequency. Now I obtained this frequency ...
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If a ferromagnet has a zero resonance frequency does this mean the magnetic order is unstable?

If a ferromagnet has a zero resonance frequency does this mean the magnetic order is unstable? I'm struggling to see how resonance frequency value affects the magnetic ordering
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What is the physical interpretation of imaginary terms in the neutron optical potential model?

I'm doing a computational project on neutron scattering and I've found that if you simulate (n,n) collisions on Uranium 238, the program predicts resonances not found in experimental data. The ...
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547 views

How can a voltage across a capacitor be greater than the total voltage applied to the circuit?

I was reading about complex impedance and AC circuits, and I just came across a sentence on a website stating that the voltage across a capacitor can be greater than the applied voltage. How can this ...