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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What is the resonant frequency of liquid water?

I learned it's not 2.45 GHz. But what is it, then? In my failure to find the real value, I'm starting to wonder: does it even make sense talking about a resonant frequency of water molecules?
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Diagonal patterns in a Chladni plate experiment [duplicate]

I am an undergraduate student that's taking physics classes and have been assigned a seminar concerning Chladni figures. I understand the theory behind it, the standing waves in 1D and 2D, Bessel ...
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Are there materials that strongly (macroscopically) vibrate under light of certain frequencies? If so why?

Picture an imperfect plane of loose particulate matter like sand or silt. Are there materials where if I shine light (not isotropically) on the plane I could get the particles to vibrate with large ...
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How could this person have discovered the resonant frequency from this string of magnets?

I stumbled onto this page http://mylifeisaverage.com/story/1364811/ and the post states that they were all making strings and shapes with these sets of 216 really small spherical earth ...
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How does the tuner really work in a crystal set?

I would like to know how and why the tuner works in a crystal set radio. I already know all the theory and the "formal definitions" (this creates a resonant circuit which responds to an alternating ...
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149 views

In an RLC series circuit on resonance, how can the voltages over the capacitor and the inductor be larger than the source voltage?

Consider an RLC circuit in series, of the form If the source drives the circuit in AC at the resonance frequency $\omega =1/\sqrt{LC}$, the peak-to-peak voltages on the capacitor and the inductor, ...
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For series LCR oscillations (resonance), why does current have to be maximum?

I learned about a year back that systems will go into oscillations with high amplitudes if the frequency of the forced oscillations coincide with the natural frequency of the system leading to ...
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30 views

AFM cantilevers driven below resonance?

Is there a physical reason why AFM cantilevers are driven below their resonance frequencies? In all of the AFMs I have used, once you measure the resonance frequency of the cantilever, it is set up ...
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15 views

Local nuclear magnetic field compared to macroscopic field

In an NMR experiment, I the local magnetic flux density of an iron sample was found to be roughly 33 T, by checking for a resonance frequency of the magnetic dipoles. How can it be that such a high ...
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32 views

Resonance of a system featuring a collection of individual resonators?

Suppose you had a number of harmonic oscillators, each with different resonant frequencies in a system. Does this imply that their is an overall system resonance that is dependent on the individual ...
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Resonance and harmonics: change in phase difference, and force due to a non uniform magnetic field

I am doing an experiment (at school) on oscillating wires and I am following a lab script. Along the way, it asks some questions that I am supposed to answer. The only problem with this is that we ...
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65 views

Trying to understand why energy must be quantized/discrete

So I'm reading about bound systems right now in my quantum text. It is beginning to explain why energy must be quantized, and is doing so by introducing the reader to the one dimensional "quanton in a ...
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Phase difference of driving frequency and oscillating frequency

If a mass is attached to a spring and is oscillating (SHM). If a driving force is applied it must be at the same frequency as the mass's oscillation frequency. However I'm told that the phase ...
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46 views

Random or Frequency Sweep

Given a resonator. I'd like to excite it but I only know a range of possible resonance frequencies ($\pm 10\text{ Hz}$). What is the most effective way to excite my system? Irradiating my system ...
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172 views

Why is the energy stored in a driven oscillator equal to the product of friction dissipated power $P_\text{fr}$ & decay time $\tau$ at resonance?

This is an excerpt from Waves by Frank S Crawford Jr. [...] At steady-state the time-averaged power must equal the time-average of power dissipated by friction. The instantaneous frictional force ...
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why do tall buildings have low resonant frequencies?

I know that tall buildings have low natural frequencies, hence they're more vulnerable to earthquakes, but why do they have low natural frequencies?
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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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37 views

Connecting two antennas to provide signal

Problem: I am in a room without FM signal. I would like to provide FM signal to the room. If you have a hole for coaxial cable, which can connect a place with signal and the room, is it possible to ...
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29 views

resonance frequency of a cylinder fixed on a wall from one side

How can we calculate the resonance frequency for a cylinder fixed horizontally to a wall from one side ? it is not bar or cantilever
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Where exactly is the antinode of an air column with open-closed boundary conditions?

Suppose that I have an air column with closed-open boundary condition. The air pressure at the open end of the tube is constrained to match the atmospheric pressure of the surrounding air. ...
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Reflection of Sound wave (Pressure Wave)

I want to study about the phenomenon of reflection of pressure waves as in an open ended organ pipe. Please suggest a suitable resource? I know about the harmonics in a stretched string and I can use ...
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77 views

Forced damped harmonic motion, angular frequency at which amplitude is maximum. differentiation [closed]

$$A_0 = \frac{(F_0/m)}{\sqrt{(\omega_0^2-\omega_d^2)^2+b^2\omega_d^2/m^2}}$$ How would I differentiate this with respect to the driven angular frequency (equating to zero) in order to obtain the max ...
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Loaded Quality Factor

I came up with an expression for the reflected power of a resonator: $$\left| \Gamma \right|^2 = 1 - \frac{1-\left(\frac{\kappa - 1}{\kappa + 1}\right)^2}{1 + 4 \left( \frac{Q_U}{(\kappa + 1)} ...
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How can the choice of wood make a good violin?

We always hear about some really fine and expensive wood that is used to make guitars, violins and other musical instruments. What's the physics behind this? What parameters (e.g. bulk modulus etc.) ...
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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 ...
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57 views

What happens when the frequency of light propagating through a solid equals the resonance frequency of the electrons in the atoms? [closed]

I was reading this article and the following questions came to my mind: During the propagation of light through a solid, the photons collide with the atom making the electrons vibrate. What happens ...
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Does resonant inductive coupling work in the presence of a strong magnetic field?

Does resonant inductive coupling work in the presence of a strong magnetic field? I am unsure because resonant inductive coupling uses magnetic fields to transmit power wirelessly and a strong ...
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Resonance and natural vibrations in vacuum

In my Physics textbook, it says that if two pendulums of the same natural frequency are placed next to each other and if one is set into vibration, the other starts resonating and when the first one ...
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186 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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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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Confusion about the resonance

I get confused with the concept of resonance. Many materials suggest that in order to achieve resonance, the system must undergo simple harmonic force ($F=F_0\sin(\omega t)$), and at the natural ...
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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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62 views

Why is permittivity or permittivity negative in certain metamaterials?

I read some papers and I think the explanation is that the driving electric (magnetic) field leads the response by π, thus making the effective permittivity (permeability) negative. But my question ...
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Why, when one opens 1 car window, does that noise occur?

When you're driving and you open 1 car window, say the front one, there comes a horrible noise, but when you open another window just the slightest bit, this noise goes away (I'm sure most people know ...
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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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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) + ...
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Textbook explanation of the resonant frequencies of molecules

An online source stated that molecules have resonant frequencies and then vaguely said that university textbooks should be consulted for more information. Another source contradicted the first in ...
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Why in particle physics the background of resonance is a decaying exponential?

When in particle physics they plot the mass histogram we see a resonance on top of a decaying exponential background? Why is the background modeled to be that way? what is the physical explanation? ...
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What determines the point of energy spillover to higher modes of a standing wave resonator?

One of the better known physics demonstrations for standing wave resonance is the singing rod . By holding the rod exactly in the middle the demonstrator constrains the first mode of excitation - the ...
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How to assess the acoustic power gain of resonnators (openended waveguides and Helmholtz)

I'm looking for a way to link acoustic power gain and time delay to geometries for these kind of resonnators. The botttom idea would be to design and 3d print an acoustic guitar that does not rely on ...
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65 views

Resonance Stabilization of a mass-spring system

Given point-masses connected by loss-less springs and a specific initial kinetic energy distribution. What mathematical tools exist to analyze the system for resonance stabilization. This problem ...
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1answer
46 views

Does the significance of frequency domain imply the resonance?

Two mobile phone, A and B, are placed on the top of a wooden desk without direct contact, the gap between these two phones is about 5 centimeters. When A is vibrating, e.g., a call comes in, a time ...
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Sonic boom and resonance

Can the damage caused by sonic booms be seen as an example of resonance? that is, when the driving frequency (be the sound wave) is equal to the natural frequency of the glass being damaged?
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EmDrive Cavity modes

The EMDrive described in patent application GB 2493361 is a simple section of a sphere surrounded by a superconducting cooling system. I have attempted to solve the oscillation modes possible and ...
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36 views

Muting a bell with a resonating object

I recently moved into an apartment next to a church with bells and since then I haven't stopped dreaming of ways to mute them. I've been thinking about a design but I'm a little unsure of the ...
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1answer
64 views

Undamped Resonance of a Classical Harmonic Oscillator

Consider an undamped harmonic oscillator. It may be driven at it's natural frequency, $\omega_0^2 = \frac{k}{m}$. According to Feynman, and other sources, were this to happen, the amplitude of the ...
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249 views

Why does at resonance only, potential energy is equal to kinetic energy?

At the steady state, the average stored energy is given by $$E = \dfrac{1}{2} m\left\langle (x')^2\right\rangle + \dfrac{1}{2} m{\omega_0}^2 \left\langle x^2 \right\rangle$$ They become equal when ...
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What is the qualitative cause for a driven oscillator to have a max. amplitude during resonance?

The steady-state motion of a driven oscillator is given by;$$x =\underset{\text{amplitude}} {\dfrac{F_0}{m({\omega_0}^2 - {\omega}^2)}} \cos\omega t.$$ As we see, the amplitude becomes maximum when ...
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What is the essential difference between a resonance and a particle?

Let me start by explaining my particle physics background is very patchy, so this question may not be as coherent as I would like it to be. In general terms, what is the difference between a ...