# Tagged Questions

Frequency is the rate of repetitive aspect in the amplitude over a given dimension.

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### Determination of nature frequency and differential equation of vibration of Hartnell governor?

I found this solution for the nature frequency but here it does not include the Ball weight and centrifugal force in the moment balance equation about the pivot (O), it is wrong answer...is not it? ...
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### Beats: frequency of resulting wave vs. beat frequency

The beats frequency heard from the interference of two sound waves with frequencies $f_1$ and $f_2$ is $$\nu=|f_1-f_2|$$ Nevertheless the frequency of the resulting wave is not $\nu$ but the mean ...
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### Conditions to find standing waves harmonics

I came up with a doubt on standing waves conditions. The type of question I find difficult to answer is of the following type. Consider a rope. I do not know if the rope is fixed at both end or at ...
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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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### Is measuring the speed of light using energy and wavelength cyclical?

I would like to measure the speed of light by directly measuring the frequency and wavelength of a light source. In order to determine the wavelength, I wanted to use a diffraction grating and the ...
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### Bohr frequency of an expectation value?

Consider a two-state system with a Hamiltonian defined as \begin{bmatrix} E_1 &0 \\ 0 & E_2 \end{bmatrix} Another observable, $A$, is given (in the same basis) by \begin{bmatrix} 0 &a \...
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### Why do you only hear the bass when someone nearby is wearing earphones?

When someone nearby is listening to music through earphones or headphones, usually you can only hear the bass (unless it's really loud where you can hear the singer's voice and the other instruments ...
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### Frequency shift due to acceleration of the source towards the receiver [closed]

How does acceleration of the source towards the receiver change the frequency shift? If a source of sound is accelerating towards the receiver, what should be the graph of frequency due to Doppler ...
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### Pound-Drever-Hall frequency stabilisation technique

I am having some difficulty understanding the Pound-Drever-Hall frequency stabilisation technique, when locking a laser to a stable cavity. As far as I understand: We emit the laser frequency, f0....
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### Humans Voice Frequency? [closed]

Do all human beings have a different voice frequency like they have different finger prints? as all of us are unique so probably our vocal folds make different vibrations while saying a same word that ...
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### How does cavity resonance produce EM waves? [closed]

My understanding is it acts like a capacitor and inductor in a loop. The capacitor releases stored energy which is absorbed by the inductor through a magnetic field which then returns it to the ...
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### Why does a remote car key work when held to your head/body?

I was trying to unlock my car with a keyfob, but I was out of range. A friend of mine said that I have to hold the transmitter next to my head. It worked, so I tried the following later that day: ...