Noise Definition and 474 Threads

my a/c-heater unit thing in my dorm is making this very irritating high pitched noise. maintenance can't hear it. so i need to prove that it's there (this is important because i live in a 12 month dorm and will be here this winter). are there any programs or devices that will measure frequency...

i was wondering if anyone could explain the circuit at he following link http://www.synthfool.com/schematics/polynoise.gif

i am trying to find a circuit diagram for a noise generator that can change between all the colours of sound. it is driving me made and was wondering if anybody can help please

Hi guys I'm currently working on a university experiment trying top create acoustic crystals. We're using a white noise generator to generate sounds at all frequencies. However I'm unsure exactly how a white noise generator creates the random signal. Can anyone explain how the an analogue...

I've been watching a discussion on another forum regarding the use of loud horns to deter dogs from chasing bikes. Some dissenters say that it is cruel since dogs can "hear so much better than humans" and such loud sounds can injure them. My question is, is it better stated that dogs have a...

How loud does brown noise have to be for it to be effective?

what are all that noises on passenger jets when flying with full load of passengers ? I thought it going to be really quiet on board but there is so much noise that one can't hardly sleep on board.

Hi, i have problems differentiating these two terms. can anyone give some examples of these two terms? Thanks!

I am reading about galaxy surveys. I want to know what is shot noise ? how we estimate it into real and Fourier space ? I am basically reading astro-ph/0503603 & astro-ph/0503604. I am not able to solve exercise 4, 5, 6. I will be thankful, if anybody can provide me some reference.

What do these terms mean. I am doing static analysis using fea on some parts. But what do automotive people do in NVH. Please give examples

Hey, I never used to like electronics, but after doing a unit last semester it has really interested me. I've gone out and bought simple circuit components and have built a whole heap of simple circuits just because I wanted to learn more of how things behave. Anyway I still have the notes...

During my work of space vehicle orbit determination, I have been confronted with a difficulty that hasn't been solved until now. When calculating the transition matrix that translate the process noises to the state parameters of position and velocity,how can I work out the partial derivatives of...

During my work of space vehicle orbit determination, I have been confronted with a difficulty that hasn't been solved until now. When calculating the transition matrix that translate the process noises to the state parameters of position and velocity,how can I work out the partial derivatives of...

My computer makes an ambulance like noise every 5 or ten minutes. Any idea what this could be?

Active/Passive noise control hi everyone, I am currently working on a project to reduce noise in AC/Heating systems in airplanes. As reference am using some literature in Engineering Noise Control and some research papers on Active/Passive noise control. I am currently searching for some...

hi everyone, I am currently working on a project to reduce noise in AC/Heating systems in airplanes. As reference am using some literature in Engineering Noise Control and some research papers on Active/Passive noise control. I am currently searching for some information on; if there are...

Well, you know the question. :smile:

http://www.indystar.com/articles/2/133270-5162-009.html

I am in the process of writing a report on the Physics of Jet engines and I have come across a problem I cannot comprehend. In the exhaust of many jet engines they allow the atmospheric air to mix with the air from the engine to reduce exhaust noise. From what I understand this allows the...

hi, I would like to know why dirak-delta function is used in autocorrelation in a way that the following is true: <å(t)å(t')>=2Dä(t-t') where å(t)is Gaussian white noise and D is the strength of the noise. Dora

A star was measured to have an apparent magnitude m=16 with S/N=10 integrated over a minute. What is the uncertainty in the measurement? signal=flux*area*time noise=sqrt(signal)=sqrt(fAt) So, S/N=sqrt(fAt) How can I find fA? m=-2.5logfAt+K 16=-2.5log(fAt)+K Hoping that K is arbitrary...

1. Identify the princible stakeholders who could be affected by noise pollution. 2. There is a rock concert planned. The convert will be held in an outdoor park, which boders both a resedential as well as a group of commercial businesses. In a town hall meeting, develop a course of action...

[SOLVED] Question on Reducing Dark Noise in Photodiodes I realize that this is more of a technology question than a physics question, but our technology forum seems to have been overrun by computer nerds. Anyway, I am wondering if it is possible to reduce the dark current of a diode by placing...

Not sure if this is more a question for the physics forum or here, but ill start here. I've been doing some reading on signal to noise calculations for video applications. In the reading it says that when you drop a certain signal by 2, the noise portion of it will only drop by sqroot(2)...