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.

Resonance is a characteristic of physical systems having some bounded structure in space that allows energy to flow between various states at specific, oscillatory rates (resonant frequencies). For a stable, resonant system at steady state the internal energy is either fixed and without loss or the rate at which energy enters the system is equal to the rate at which energy is lost.

Examples of resonant systems include mechanical structures like bridges and buildings, electrical, circuits like radio transmitters, musical instruments like the flute, thermoacoustic oscillators,and biological structures like the semicircular canals of the human ear. Resonant systems thus encompass a very broad spectrum in different types of energy flow and are found in many types of physical systems.

Resonance is also seen at all scales of nature from the nucleus of atoms to the expanse of galaxies.

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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 using only 1 prong? Can a single prong not…
acadien
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Why does our voice sound different on inhaling helium?

This question (and answer) is an attempt to clear the air on what appears to be a very simple issue, with conflicting or unclear explanations on the internet. Arguments, negations, etc are invited. I'm classifying this as a physics question, since…
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Why is Microwaved mac & cheese burnt where they touch?

After reheating cold about 1.5 oz. of Annie's Mac & Cheese shells for 15 seconds on high power in the microwave, the mac & cheese was burnt black only at certain points where the pasta is touching each other. Does anyone have an idea of what might…
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Why do string instruments need hollow bodies?

My textbook states, 'The sound box has a large area, it sets a large volume of air into vibration, the frequency of which is same as that of the string. So due to resonance a loud sound is produced.' My question is why isn't the air around the…
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Why does pitch increase when you blow harder into a whistle?

When you play recorder or whistle, the pitch depends on how hard you blow into the tube. E.g. when you blow a whistle, initially the pitch is slightly lower when there is less air flow. This seems counter intuitive since the airflow should only…
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Intuitively, what actually is the cause of resonance?

Please don't explain it mathematically. I have been searching for the reason for a long time. I have watched Walter Lewin's video giving an example of resonance, but I didn't get the reason behind the intuition. I am confused if the reason exists.
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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 vibrations. What is the theory behind this fact? Are…
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Does amplitude really go to infinity in resonance?

I was recapping the forced oscillations, and something troubled me. The equation concerning forced oscillation is: $$ x=\frac{F_0}{m(\omega_0^2-\omega^2)}\cos(\omega t) $$ I don't understand why this equation predicts that the amplitude will…
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Why does blowing a whistle in someone's ear damage it more than blowing directly in their ear? Won't the whistle reduce overall energy?

If I blow really hard from a whistle near someone's ear, it'll hurt a lot. But if I blow directly at a person's ear, it won't hurt nearly as much. But shouldn't the whistle (or any other obstruction) strictly reduce the amount of energy hitting the…
chausies
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How does a violin produce notes, microscopically?

I believe this question would have been asked before, but not like this. The popular answer to this question is that the slide-release action of a bow sets up vibrations in the strings, of which ultimately only the resonant frequencies would…
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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, but is that enough to dampen it entirely? What…
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Non-resonant but efficient frequencies

I understand that if the frequency of a driving force coincides with the natural frequency of an oscillator (say a pendulum), the rate at which energy is transferred to the same is maximized. However, there may be other frequencies that are not so…
Sierra
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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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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, surely a 3-pronged tuning fork would be even more…
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Resonances in high energy physics

I still do not understand what a resonance precisely is. Is it exactly the same as a particle? Or only an excited state? And why does it make a peak in some diagrams? And which diagrams?
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