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What is this called? (Warning - mathematics involved)

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Hi all,

I'm looking for the English word to describe a mathematical phenomenon.

When you superimpose two (co)sines of slightly different frequencies (say, y1=sin(9x) and y2=sin(8x) or something), the resulting waveform consists of periodic blob-kind of thingies, the amplitude kinda like a waveform itself.

In Dutch, it's called "zweving" which literally means floatation, but I doubt it's called that in English.

Alphons
And five hundred entirely naked women dropped out of the sky on parachutes.
-- The Hitchhiker's Guide to the Galaxy

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dissonance, is the term that comes to my uneducated mind. The sum of the difference. For example: if a twin engine jump plane pilot has the left engine producing a 220Hz and the right producing a 225Hz, one would hear a 5Hz wawa. Assuming one listened.

Or maybe resonance would be better now that I reread your post. That is when 2 overlapping wave forms peak periodically at the same time.
take care,
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if a twin engine jump plane pilot has the left engine producing a 220Hz and the right producing a 225Hz, one would hear a 5Hz wawa. Assuming one listened.

Nice example

Btw: I finally managed to find a reference. The word I was looking for is "beat(ing)", apparently.

Thanks,

Alphons
And five hundred entirely naked women dropped out of the sky on parachutes.
-- The Hitchhiker's Guide to the Galaxy

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Sorry that my englisch is leaving me. The word you want is "Harmonics".
take care,
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Heterodyne, perhaps?

When two frequencies are heterodyned together, the output is the sum and difference of them.

mh
.
"The mouse does not know life until it is in the mouth of the cat."

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Hi all,

I'm looking for the English word to describe a mathematical phenomenon.

When you superimpose two (co)sines of slightly different frequencies (say, y1=sin(9x) and y2=sin(8x) or something), the resulting waveform consists of periodic blob-kind of thingies, the amplitude kinda like a waveform itself.

In Dutch, it's called "zweving" which literally means floatation, but I doubt it's called that in English.

Alphons

EEs would call it heterodyning, physicists and musicians would call it "beats" or "beating", mathematicians call it a superposition of two waves.
...

The only sure way to survive a canopy collision is not to have one.

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wawa works for me.

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Phase harmonics.
People are crazy. Cuz there's more of 'em.

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Hi all,

I'm looking for the English word to describe a mathematical phenomenon.

When you superimpose two (co)sines of slightly different frequencies (say, y1=sin(9x) and y2=sin(8x) or something), the resulting waveform consists of periodic blob-kind of thingies, the amplitude kinda like a waveform itself.

In Dutch, it's called "zweving" which literally means floatation, but I doubt it's called that in English.

Alphons

It is called beating, and the frequency between the maxima of the superimposed sine waves is the beat frequency

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Are you talking about a point, where two limits meet, however right before meeting, they go crazy?
Its a good day to LIVE, why puck up a good thing.

There is no reply in aad section for. " hell no i would not put an AAD on my back"

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Quote

Hi all,

I'm looking for the English word to describe a mathematical phenomenon.

When you superimpose two (co)sines of slightly different frequencies (say, y1=sin(9x) and y2=sin(8x) or something), the resulting waveform consists of periodic blob-kind of thingies, the amplitude kinda like a waveform itself.

In Dutch, it's called "zweving" which literally means floatation, but I doubt it's called that in English.

Alphons

EEs would call it heterodyning, physicists and musicians would call it "beats" or "beating", mathematicians call it a superposition of two waves.

Now I come to think of it, short wave radio hams in the old days used to use this technique to detect morse code sent with carrier wave (CW) only. The gizmo on the ham radio was called a Beat Frequency Oscillator or BFO. It would create an audio signal when mixed with the incoming radio frequency (inaudible) carrier. It is also used to make audible the station ID on aircraft VOR and ILS navigation radios.
...

The only sure way to survive a canopy collision is not to have one.

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In techno / club music it's called DJ Shoes-in-the-dryer. AKA DJ Trainwreck.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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