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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Efficiency of resonant inductive coupling as a function of distance

What is the relationship between the efficiency of energy transfer between resonant inductive coupling between two coils, and the distance between the coils?
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How is energy conserved in resonance?

According to Wikipedia, [...] resonance is a phenomenon that occurs when a vibrating system or external force drives another system to oscillate with greater amplitude at a specific preferential ...
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Physics of waves under an ice road

As wikipedia writes, While easier to drive across in the winter than land, roads over water present a great danger to anyone using them. Speeds are typically limited to 25 km/h (16 mph) to prevent ...
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How much energy would it take to take down a 747 using vibrations? [closed]

Background Information: All materials have a resonant frequency, which is the frequency at which they are most easily excited (vibrated). That's how glass is shattered using high-pitched sounds. ...
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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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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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Parallel RLC circuit, how branching currents may each be larger than source current at resonance?

How can the branching currents individually be greater than the source current?
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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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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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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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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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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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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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Trying to understand why energy must be quantized/discrete [duplicate]

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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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 with ...
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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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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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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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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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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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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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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. Therefore,...
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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)} \frac{\...
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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 $$Q(\omega)=\frac{V_\text{max}/...
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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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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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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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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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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) + (a-b\cos{...
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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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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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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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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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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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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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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 ...
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Resonance in Benzene violating Second Law of Thermodynamics

In chemistry a few months ago we were taught the resonant structure of benzene, that states the double bonds upon the six carbon atoms flicker back and forth between the two possible states it can be ...
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Materials that change their natural frequency

Say I have some material (solid, liquid, plasma, etc.). It has a set of natural frequencies. Now I pass a wave through it (sound, light, etc.). Once I pass the wave thought it, the material has a ...
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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 ...