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Interesting question. Note that the power transfer is $$P=\frac{1}{\tau}\int_0^\tau F(t)v(t)\,dt$$ where $F(t)$ is the applied force, $v(t)$ is the velocity of the oscillation, and $\tau$ is the length of the period of the oscillation (this is just a simple extension of the usual rule for work, $w=Fd$, to time-varying systems). The usual forced oscillator ...


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Yes, the out of phase wave interferes with the source wave and cancels itself out. What you don't want, is when the ground moves to create standing waves that go up and down on the building adding energy and eventually breaking things. So a tuned mass damper will remove energy of a particular frequency using the concept of mechanical impedance matching ...


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The reason why the tuning fork creates a sound is because it makes the air molecules around it vibrate, which means that there is a longitudinal sound wave created. If I understand correctly, the bottom of your tuning fork was placed into a wooden block and then struck with a hammer. The wooden block does not actually resonate (the frequency of the tuning ...


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You are correct. When the forcing frequency is equal to that of the natural frequency then the external force is constantly doing positive work on the system, which results in resonance. When the forcing frequency is not equal to the natural frequency, then there are times when the force is contributing positive work (adding kinetic energy), and times when ...


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It was already mentioned by Carl Witthoft, but I think the ocarina does count, as long as you're not too hung up on the resonance chamber being a tube as such. From Wikipedia: The ocarina, unlike other vessel flutes, has the unusual quality of not relying on the pipe length to produce a particular tone. Instead the tone is dependent on the ratio of the ...


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Your equation is Newton's second law. That's always true for any system in Newtonian mechanics. So it's very straightforward to figure out which equation of motion applies to this system: write out $\sum F = ma$, plug in the forces, and simplify. Now to address the other issue: does a constant force qualify as a driving force? I'd say there are two ways to ...


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You don't explicitly state you are looking for a wind instrument so perhaps a drum would count. Perhaps a snare drum since the snare is on the resonant (non-struck) head or a kettle drum maybe qualifies as a pitched instrument. If you are looking for a wind instrument in particular and Carl Witthoft's suggestions of the ocarina or the jug do not fit the ...


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Well, does playing flute-like across the top of a beer bottle count? Or, better put: a jug-player in a country "Jug band" plays his instrument that way. It's also your call whether blocked instruments with holes along the length qualify, such as an ocarina. I sort of guess what you're looking for is an instrument with an air pocket as the resonance, as ...


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I'm having trouble understanding what you're trying to say, but assuming you're just looking for period resonances of the form $a:b$ where $1\leq a,b\leq 5$, the following 4 lines of Mathematica code using your example list of extrasolar periods should suffice: A = {0.44, 0.8, 0.9, 0.9, 1.2, 2.0, 3.0}; n = Length[A]; d = 0.05; ResonanceMatrix = ...



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