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Measurements on the topic for this forum can be done by holding a $8 tuning fork in front of a mic, then analyze the sound file with the free program "SpectraLabs" using the "Waterfall" display and using the built in Goertzel frequency extraction algorithm. That will give accuracy to around 0.01Hz. This website does not allow me to post ... 0 All physical harmonic oscillators will change their frequency versus the amplitude of oscillation, (even precision pendulum clocks). If the tines of a tuning fork are struck very hard the frequency will drop because the tines have farther to move and; though the internal restoring force also increases with displacement, it will not be enough to exactly keep ... 1 Gravity pulls stretching the spring down to a new equilibrium position. This equilibrium stretch gives an upward force which balances and cancels the gravity force. The mass when disturbed from the new equilibrium always pushes back toward equilibrium. The Hooke proportionality is still the spring constant k assuming the spring didn’t get stretched too much ... 0 With a mass hanging on a spring, the only effect of gravity is to determine the rest position. Damping is caused mainly by friction with the air which is always opposite to the direction of motion, and possibly to heat generated in the spring as it undergoes flexing. 1 How did the liquid levitate at 0:37 or at any one of those moments ? The liquid levitates because the gauge pressure of the gas pushing up on the bottom surface of the liquid is equal to the weight of the fluid on average. This is essentially the same reason a hovercraft levitates. I think it's because of vibrating the air in the vertical direction which ... -1 when you apply vibrations and then flip the liquid then due to vibrations no droplets are formed and high surface tension of the liquid doesn't allow mixing of anything in it easily so some particular density may allow that to happen but some completely block the mixing of the air 3 In general relativity, any test particle's worldline (whether the particle is massive or massless) is determined entirely by its initial four-velocity$u^\mu$, and not by any other properties. This is manifested by the geodesic equation $$\frac{d u^\mu}{d\tau} = \Gamma^{\mu} {}_{\rho \sigma} u^\rho u^\sigma.$$ From the properties of ordinary differential ... 1 In circular motion we user the Greek letter$\omega$(omega) to represent angular velocity, so the angle$\theta$travelled through at time$t$is$\theta = \omega t$Typically$\omega$is in radians per second, so the time taken to complete one rotation is$\displaystyle t_{rot} = \frac {2 \pi} {\omega}and the reciprocal of this is the frequency of ... 0 I think I might know what you are asking. You believe that because circular motion and SHM are physically different, then why do we use mathematical equations and things like frequency and angular velocity etc to describe the both of them? Well they might be different physically but are mathematically similar. Picture an object in uniform circular motion on ... 1 what is the need to use the same variable for angular frequency as that of angular velocity that we use in different concepts? Honestly as long as you know what you are talking about, you can take up any variable as per your convenience. It does not matter. If it is bothering you so much, then use english letter "W" for angular velocity and Greek ... 0 Considering electric circuits, the Voltage is an analogy for force in mechanical systems. The inductor, capacitor and resistances are analogs to mass, spring constant and damping respectively. The frequency of forced vibration is simply the frequency of the AC voltage. At steady state after all the transients are died out, the energy for the system is ... 2 I agree that this description of forced oscillations is too short and too little - it is confusing more than explaining. Let us go point by point: First of all, let us note that the machanical system implied here is an oscillator, most likely a linear oscillator which has its own natural frequency (and probably also a damping coefficient) Periodic force ... 0 First you need to track the center of mass of the object in position, velocity and acceleration. Use the chain rule from calculus to differentiate with time. Position \begin{aligned} x & = \mu + \ell \sin \theta \\ y & = - \ell \cos \theta \\ \end{aligned} Velocity\begin{aligned} \dot{x} & = \dot{\mu} + \ell \dot{\theta} \cos \... 1 We can start off with just the pendulum. Info #1: length and mass of object given. Natural frequnecy (\omega_0$) of the free pendulum can be found out. Info #2: when$\omega = 0$, from this frictional coefficient of the oscillatory system can be found out. Now, if the top of the pendulum is undergoing an acceleration(like in a car maybe) then we see that ... 0 The answer to your question is quite "simple". The energy difference between two arbitrary energy levels is associated with a photon that has the same energy as this difference:$E_{photon}=E_{level1}-E_{level2}=\hbar\nu$. So the frequency is nothing else than the frequency translated inro the energy of the photon. To put it even better: the energy ... 2 Yes the electrons do oscillate during the transition. I don't think you can get this from the Bohr model, but in simple QM it follows nicely. Suppose an electron with charge$q$starts in a higher state$\Psi_2(\vec r,t)=\psi_2(\vec r)e^{i E_2 t/\hbar}$with energy$E_2$and ends in a lower state$\Psi_1(\vec r,t)=\psi_1(\vec r)e^{i E_1 t/\hbar}\$ with ...

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Since you have not provided a lot of background information, I am going to assume that you are talking about the electron transitions in the Bohr model Hydrogen atom. An electron can only occupy certain valid shells at specific a distance(radius) from the nucleus. In the ground state, the electron will be in the first shell (K-shell) and will posses lowest ...

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The claim about discovery of gravitational wave (GW) signatures in CMB were retracted, as already mentioned in the comments. Any pre-inflationary signals would be washed out (redshifted, diluted beyond observation) by inflation. As for the actual question, the spectrum of primordial GW is expected to be almost scale invariant, i.e. nearly equal emissions for ...

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I think that as far as wave mechanics go, energy (strength = energy) put into a system usually correlates with amplitude, not frequency. I'd support this claim by using logic; a tuning fork would be useless if energy dictated frequency, because every time you hit the tuning fork you'd hear a different frequency, and you can't guarantee that you'll hit the ...

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Does the frequency of a tuning fork depend on the strength by which it is struck? No. To a first approximation, a tuning fork’s frequency is determined by its mass, stiffness, and shape, which are fixed. The approximation is good for weak strikes; if you strike it really hard, the approximation becomes worse and it can affect the frequency, so be gentle ...

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Normally, when you restrict the size of a passage through which a wave can propagate you increase the cutoff frequency because you need "roughly" a wavelength's worth of free space to fit a wave inside. A metallic piece inside the waveguide restricts the wave because there is no propagation inside an ideal metal. This is unlike in a dielectric ...

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