# Tagged Questions

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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### 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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### Why do tuning forks have two prongs?

I believe the purpose of a tuning fork is to produce a single pure frequency of vibration. How do two coupled vibrating prongs isolate a single frequency? Is it possible to produce the same effect ...
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### Theory behind patterns formed on Chladni plates?

In this video of vibrating Chladni plates we can see small sand particles align themselves into different interesting patterns (also shown in the image below) which correspond to some particular ...
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### Why don't tuning forks have three prongs?

I was reading Why tuning forks have two prongs?. The top answer said the reason was to reduce oscillation through the hand holding the other prong. So if having 2 prongs will reduce oscillation loss, ...
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### 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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Consider a forced, damped harmonic oscillator $$\ddot{\phi} + 2\beta \dot{\phi} + \omega_0^2 \phi = j(t) \, .$$ If I pick a sinusoidal driving force $j(t) = A \cos(\Omega t)$, I find $$\phi(t) = \... 2answers 12k views ### 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 ... 2answers 629 views ### 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 ... 1answer 622 views ### What's the difference between NMR and EPR? Both NMR and EPR describe the response of magnetic spin to external field. When collecting data, how do you know you're looking at nucleus spin flip or electron spin flip? In other words, since every ... 1answer 20k views ### Science behind the singing wine glass A wine glass filled with water (approximately half or a quarter), when you use a wet finger and rub the top of the wine glass, the wine glass will produce a sound. I heard that it is because of the "... 2answers 206 views ### Physical reason behind having greater amplitude when driving frequency <  natural frequency than that when driving frequency > natural frequency This is quoted from A.P.French's Vibrations & Waves: If the driving force is of low frequency relative to the natural frequency, we would expect the particle to move essentially with the ... 3answers 9k views ### 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? 2answers 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? 5answers 185 views ### 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 ... 2answers 378 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 ... 4answers 6k views ### How does radio receives signal from particular station? When you tune your radio (digital or analog) to receive say 100 MHz frequency and while in the environment there are hundreds of channels everywhere around the radio. How does it chooses to receive ... 2answers 1k views ### 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 ... 1answer 330 views ### The Solar System explosion in the Nice model This video depicts one variant of the Nice model (pronounced "neese", like the city in France). I'll briefly describe it in case the link ever dies. Here is the initial configuration: The four ... 1answer 804 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 ... 1answer 96 views ### 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,... 2answers 408 views ### How might a resonant antenna and black body radiation interact? How does an antenna behave when it is cooled so that its black-body radiation is emitting energy at its resonant frequency? Edit: To clarify, its not how they're related in general, but how might ... 2answers 118 views ### Standing sound wave in a wind instrument So I've had this question bugging me ever since I saw sound at physics class: How is it possible to match the resonance frequency of a column of air in an organ pipe and form a standing sound wave by ... 3answers 2k views ### Does the Breit Wigner formula apply to intermediate virtual particles? Breit Wigner Formula describes the cross section for interactions that proceed dominantly via a intermediate particle (O*) A+B → O* → C + D:$$σ = \frac{2\Pi}{k^{2}}\frac{Γ_{i}Γ_{f}}{(E-E_{o})^{2} + (...
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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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### An analogy for resonance?

I learned that the phenomena of resonance occurs when the frequency of the applied force is equal to the natural frequency of an object. At this point, an object vibrates with maximum amplitude. How ...
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### Resonating frequencies of atoms

I have a mathematics and computer science background with very little physics. I have read that the resonating frequency of an atom of some element is always exactly the same as the resonating ...
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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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### 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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### Resonant inductive coupling and Schumann resonances

I was reading about WiTricity (http://en.wikipedia.org/wiki/WiTricity) a technology developed by MIT to wirelessly transmit electricity through resonance, and I have this question: Given the ...
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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, ...