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

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379 views

Frequency of touch, taste, and scent [closed]

So I was thinking about sound - and how anything below 20Hz is basically inaudible to humans (because it is too low of a frequency to be recognized), as well as anything above around 20KHz (because it ...
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1answer
80 views

Does sound absorption depends upon the amplitude of sound wave?

I can understand the mechanism of frequency dependant sound absorption by most materials but does the sound attenuation also depends upon the AMPLITUDE(sound pressure or rather loudness/sound ...
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2answers
138 views

Does the Sun produce audible sound?

Theoretically if I were able to build some sort of device that let me sit 1 foot away from the surface of the Sun (or any star for that matter) without being vaporized, would a star produce any sort ...
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1answer
225 views

Are small speakers inherently limited to higher frequencies?

I am hoping to build a subwoofer using multiple smaller speakers (165mm) instead of a single larger speaker (380mm). My theory is that the displaced air volume is what matters, not the individual ...
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2answers
35 views

Rotational Velocity and Rotational Frequency

What is the difference between rotational velocity & rotational frequency? Their units seem to be the same, and I've read that one is a 'scalar' and the other is a 'vector,' but how do they ...
0
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1answer
39 views

Horsepower at certain RPM point without knowing torque?

I want to know the horsepower produced by an engine at certain RPM by knowing another certain RPM point? Let's suppose that an engine produces 200 hp at 4000 RPM, how many horsepower is produced by ...
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1answer
210 views

Will a sound composed of the frequencies 450Hz, 650Hz 850Hz have a clearly defined musical pitch? Why?

According to my lecturer, the perceived pitch of a sound composed of the following harmonics: 750Hz, 1000Hz, 1250Hz is equal to the fundamental frequency which is the highest common factor of the ...
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6answers
5k views

Why can't you hear music well over a telephone line?

Why can't you hear music well well over a telephone line? I was asked this question in an interview for a university study placement and I unfortunately had no idea. I was given the hint that the ...
2
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1answer
163 views

Red color has largest wavelenght and violet minimum (in the range of visible light). then why does violet light appears reddish? RED + BLUE = VIOLET [duplicate]

My question is simple. Green light is more similar to red light than violet, then why is violet reddish and green not? in the language of frequencies and wavelengths, red and violet should contrast ...
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1answer
427 views

Calculating the energy of an electron given the wavelength

Okay, so I know that the wavelength of an electron is 5e-7m and I am asked to calculate its minimum velocity and hence minimum energy. Calculating the minimum ...
2
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2answers
120 views

Can someone please explain the “infrared catastrophe”?

In my readings I've run into this idea of an "infrared catastrophe" associated with 1/f noise. As far as I can tell it is because when you graph the periodogram of the 1/f signal you see the PSD goes ...
4
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0answers
121 views

How is extremely low frequency (ELF) radiation collected by a submarine antenna?

The U.S. Navy Project ELF managed to generate extremely low frequency (ELF) radiation at down to $\approx 76$ Hz (implying a wavelength of $\approx 3,945$ km!). I was curious, what kind of receiving ...
2
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0answers
33 views

Math formula for crystal glass resonance [duplicate]

For a music therapy experiment, I have to use several crystal glasses with water and different cylindrical shapes, and make them vibrate and produce different sounds. Is there a math formula that ...
2
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0answers
516 views

How would you go about finding the natural frequencies (resonance frequency) [closed]

How would you go about finding the natural frequencies of solid materials like wood (e.g., teak, pine), stone (e.g., marble, granite) liquid, etc?
2
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1answer
99 views

Is Sound Considered a Subtopic of Physics? What are the SI Units of Sound?

Does physics cover sound? If so, why does sound not have units in the SI system, or how would we measure sounds and frequency? I guess it's debatable, but why isn't it standard practice in physics?
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0answers
32 views

help me.. please [duplicate]

I'm a total novice to physics so please forgive me but I'm looking for a starting point on sound, frequencies and everything to do with electricity. Preferably books because my internet usage is ...
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8answers
15k views

Why does a remote car key work when held to your head/body?

I was trying to unlock my car, 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: Walked away from ...
0
votes
1answer
99 views

Two masses attached by a spring [closed]

Suppose there is a system of two masses $M_1$ and $M_2$ connected by a spring with constant $K$ on a frictionless surface. What is the frequency of this system's oscillation? So I have fixed a ...
2
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4answers
352 views

Can frequency be equal to 0?

Is correct to speak about frequency equal to 0 ? $$f= \frac{1}{t} $$ If $t\rightarrow\infty$ can I consider that the frequency is equal to 0 ?
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3answers
65 views

Would it be possible to distinguish rap and singing from just seeing the soundwaves?

For any person even remotely familiar with music it is obvious that rap and singing are easily distinguishable (save for some interesting mix styles). This means that there must be a clear difference, ...
2
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2answers
57 views

Frequency of Light Near a Massive Object

We know that near a massive object, light's wavelength and frequency changes, but its speed remains same. I'd like to know how it is possible for frequency to change, unless we change the light ...
2
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2answers
105 views

How does one measure the frequency of a laser?

I am taking a short introduction course on lasers. I never knew that the frequency of a laser is so high for a given wavelength (e.g. 780nm). I am wondering how people can measure the frequency of the ...
2
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2answers
1k views

Why does noise affect FM radio less than AM?

Frequency modulated waves are less susceptible to noise compared to amplitude modulated signal. This is because the information in an FM signal is transmitted through varying the frequency, and not ...
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2answers
496 views

Why are two independent sources incoherent?

Coherent sources are produced from a single parent source. But, why are two independent sources always incoherent? Two sources can produce light of the same frequency. Then, I guess the problem is ...
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2answers
190 views

Frequencies of Matter [closed]

Is it theoretically possible for physical solid matter to vibrate at a high enough frequency to become imperceptible to vision and move through other solid matter?
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3answers
199 views

How to calculate Standing Waves in Electrical Cables?

I have a 20 metre Coaxial Cable. I send digital signals down the cable ranging from 5 KHz to 50 KHz. I have noticed a pattern in the noise ratio, an oscillating wave. I predict this is to do with ...
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0answers
38 views

Resonance force with multiple emitters

Will I get a stronger resonance if I put multiple frequency generators around the same object? example image
5
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1answer
108 views

Frequency shift without affecting signal length

Non-physicist here. From what I've learned in university and what common sense says, a shift in frequency of a signal results in a change in its length in time. For example, if a sinusoid signal of ...
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2answers
147 views

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 ...
3
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1answer
54 views

What is a Nyquist edge?

I've come to this sentence and I don't understand the term Nyquist edge. Because observing in the FM band is not feasible, a sampling frequency of 200 MHz has been chosen for most of the receiver ...
2
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1answer
355 views

Spring system - 3 DoF system and its properties while changing stiffness

I was given the attached 3 degree of freedom spring system with the purpose of analyzing it. I came up with the following equation of motion and then I ran Matlab to calculate the corresponding ...
3
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1answer
95 views

Do monochromatic waves carry information?

The answer is negative according to http://www.mathpages.com/home/kmath528/kmath528.htm It should also be remembered that a perfectly monochromatic wave carries no information, and therefore is ...
0
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3answers
206 views

Does the magnitude of an electrical field change with frequency?

I am trying to model the frequency response of a force (dielectrophoresis) that is based on gradient of an electric field. One of the components is the CM factor which has a frequency component, but ...
5
votes
1answer
98 views

Predominant light frequency over the day?

I'm not well-versed in physics, so I hope you'll forgive me if this question is significantly off the mark. I'm interested in the predominant frequencies of light over the course of one day. My ...
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0answers
32 views

How to represent a multiple in the frequency domain

So, in my previous question Where does this formula for prediction of a multiple wave come from?, I get that using this picture: we have so far written the time it takes for a multiple to travel ...
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5answers
10k views

Do low frequency sounds really carry longer distances?

It is a common belief that low frequencies travel longer distances. Indeed, the bass is really what you hear when the neighbor plays his HiFi loud (Woom Woom). Try asking people around, a lot of them ...
4
votes
1answer
195 views

Do higher frequency EM waves travel longer than lower EM frequency waves?

In radio communication, the distance traveling seems to be an important parameter before we choose the frequency band of communication. There is also a path-loss model that describes a distance ...
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1answer
128 views

Changing effective mass to lower frequency

I'm trying to scale a physical object up in size, either double or quadruple. It's a circular acrylic plate, with multiple weights attached around it's edge, to lower the resonant frequency to a ...
2
votes
0answers
88 views

What is the maximum possible frequency and wavelength?

As a start I assumed Planck angular frequency which is the reciprocal of Planck time as the frequency upper limit, but not so sure. On the other hand, is there a lower limit? Can we consider the ...
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1answer
125 views

At what frequency would a quartz crystal shatter?

Would it be possible to emit a sound at such a frequency that a quartz crystal inside of a watch would shatter? (Rendering the watch useless)
3
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1answer
148 views

What determines the form of the intensity curves in Laser-Induced Fluorescence (LIF) measurements?

What determines the form of the intensity spectra of different particle species in Laser-Induced Fluorescence (LIF) measurements? See e.g. I figure that bigger particles have more ways to get ...
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2answers
66 views

Vibrating system at angular frequency in a vibrating system

Can anyone clarify what does mean the angular frequency of a system in case of the vibrating membrane. Angular frequency is measured in radians per second, what does this have with the vertical ...
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1answer
51 views

Thinking Clearly about Fresnel Zone of Short Pulse:

Let's say you have a short pulse of light which expands radially from a lightbulb, and it impinges upon a mirror and reflects towards a photodetector which you have places somewhere above the mirror. ...
2
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0answers
431 views

Chladni Plate Mathematics

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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3answers
3k views

What is the meaning of “frequency of a human voice”?

The term frequency for a periodic wave can be defined as the number of times a repeating pattern occurs in a given time period (eg: no. of crest and trough cycles per second for EM wave). But what ...
5
votes
2answers
560 views

Why does a glass breaks when subject to very sharp sound like in opera?

I have seen in Ripleys believe it or not that an opera singer generates a very high frequency of sound and breaks a glass window.How do they do it?
5
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1answer
572 views

Does a domestic microwave work by emitting an electromagnetic wave at the same frequency as a OH bond in water?

I was told once that microwaves work by exciting water molecules in food. Also that this worked because the frequency in the microwave was the same as that in the bond between Oxygen and Hydrogen in ...
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2answers
418 views

why is a resistor frequency independent

I had a doubt that why is a resistor, frequency independent? Since, as frequency increases the movement of electrons increases so heat increases which causes change in resistance. So my question is ...
4
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1answer
3k views

How do you calculate vortex shedding frequency?

I am attempting to try to find out if there is any effect of Von Karman vortices on a group of wind speed readings where it is presumed that due to a mountain nearby the data collection spot Von ...
2
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0answers
51 views

Harmonics of an infinite cylinder

If a hypothetical cylinder was infinitely long, could it vibrate at any frequency, since any frequency would be a harmonic of it? And (less hypothetically) if a cylinder was only really long, would it ...