Sound Definition and 1000 Threads

Homework Statement A person turns up the volume on a radio. Which aspects of the motion of a point on the diaphragm must increase? a. maximum displacement only b. average speed only c. both maximum displacement and average speed d. neither maximum displacement nor average speed Homework...

I need an instrument to measure the frequency of the sound of a vibrating violin string for a high school research essay. I tried using a Labquest and a vernier microphone to measure but it was way too imprecise. I need the instrument to very accurate in measuring Hz as the nature of my essay...

For physical experiment I have a project in which I have to measure the speed of sound in the air. 1. If I take an iron tube (inside is air) and a speaker, 2. put the speaker at the beginning of a tube, 3. speaker is connected to frequency generator (with which I can change frequencies)...

c² = (n/m) ∂²U/∂n² where U = vacuum energy density as a function of the quasiparticle density n = quasiparticle number density m = bare mass of quasiparticle Is there a book, article where this formula is explained? Thank you.

Hello! I have a system depicted below. I need to know what is the working equation that governs the transmit and receive power of the transmitter and receiver in the diagram. The transmitted signal is a sound wave and not an RF signal, the transmission is underwater. I would like to know what is...

Homework Statement Determine sources of error which could have affected the results. Some background information: The lab consisted of playing a tone generated by a tone generator above a standing open-closed tube which had water in it. The first harmonic was measured through a computer system...

Why are sounds louder at night than during the day?

Suppose that an aircfract somehow is not moving. Then I would expect the sound waves it produces to spread out uniformely in a spherical fashion. Now imagine a airplane traveling at approximately the speed of sound. In this case, if the airplane produces a wave at point A and after a time T the...

When sound hits a wall,part of it gets reflected and part of it gets transmitted due to acoustic impedance difference between solid and air. My problem,and point of this question is that having material or gas impedance number is completely useless unless we know the frequency and wall...

Homework Statement Calculate the speed of sound in the classroom. You can use: Tuning forks, water, beaker, pvc pipe, ringstands, etc. Homework Equations v = f(wavelength) For fundamental frequency: L = 1/4(wavelength) For fundamental frequency: f = v/4L The Attempt at a Solution Here is...

I live in a country where people (unfortunately) have a culture of listening music at very high volume in their houses, frequently from their car. However I've been noticing that the sound some of the neighbours sound oscillates from time to time between a high volume and a "low" volume. I've...

Hi guys, I am involved in some research on modelling sound from fluids through mirco annuli and i have been trying to get some of the basic fundamentals on generation of sounds from turbulent flow. Unfortunately most of the online literature do not give much details on the physics of such...

This is a simple problem from a textbook I am reading, and everything below is written word by word and sign by sign from said textbook. Formulas given in the book just don't give the result authors claim they do: Homework Statement An input of 1 W produces a SPL of 115 dB at 1 m. What is the...

Morning! My question is this: If we consider a situation of mechanical collision, in the real world we shall observe certain loss of energy into heat or sound. Can we find mathematical equations to measure the amount of sound or heat produced using only mechanical variables, such as mass...

Hi. If I know the pitch and amplitude of a sound wave, will I be able to calculate its volume. I can understand volume of devices vary betwerb brands and other categories. For the sake of discussion, let's assume volume to be a consistent unit or if db is the right unit, let's take that.

To the best of my knowledge: a powerful oscillation at one frequency means more energy is required to make same medium oscillate at another frequency. Since sound perception works by detection of air oscillation, could a sufficiently powerful oscillation at an inaudible frequency (to humans)...

So again, I’ve got this analytical question on my mind and it’s been bugging me for a couple weeks now. So my question is, how do sound waves work? I’m talking about if you put two radios facing each other playing different songs. What would happen? Is it if waves match then they just combine...

Homework Statement Spaker located at 90 feet from a auditorium chair. The sound pressure level at the chair is 70 dB. The first reflection from the roof takes 200ms to get to the chair. What distance does the first reflection travel to get to the chair if the room temperature is 303.15 K? What...

I had a thermos flask that I had never used since I had bought it. Today, I decided to take it out and use it for storing hot water, so that I don't have to heat water every time I feel thirsty. An interesting incident occurred. I heated water to near about boiling temperature, and filled the...

Has anyone encountered the term "hypersonic sound speed" in connection with fluctuations of thermodynamic quantities in condensed matter? How is hypersonic different than regular sound?

Hello everyone, I'd ask you through an illustration which for me would be more clear to put questions I wrote in the image: Thanks to all! Cheers Luigi

If the spheres of a Newton's Cradle were perfectly spherical I assume "contact" would be some minimal distance between the outer electrons of one atom of each sphere? Pulling one sphere back and releasing would result in a modest plastic deformation and subsequent minimal distance between more...

Homework Statement Hello, If one can see the image I posted, the question that follows is this: Use the information provided to obtain a value for the wavelength of sound emitted. The signal is at maximum intensity at X, and minimum at Y. http://uploads.im/7wJOq.jpg Homework Equations Now I...

Hello, I have a question that I've been struggling to find an answer to / understand. Probably because my understanding of physics is quite limited :) Before I ask the question, these are the things I take as facts, so please correct me if something is wrong: 1. A speaker in half space...

Homework Statement Hello. I have a problem, which is as follows: A seat in a concert hall is 84 ft from the tympani. The tympanist strikesa single note. The sound pressure level of the direct sound of the note at the seat is measured to be 55 dB. The first reflection from the nearest sidewall...

Hello everyone! :-) Actually I'm starting to understand acoustics physics and I figured actually out about this equation: $$\frac{\partial^2\psi}{\partial t^2}=c^2 \nabla^2 \psi$$ which describes practically about pressure and propagation speed into space and time. I know also this equation...

So I have the opportunity to work at the University of Arizona this upcoming summer in High Energy Physics. This is an amazing opportunity since I get to spend a summer doing research at a university different than my own (although it will be unpaid). But I am wondering, how good will it be when...

Homework Statement Organ pipe sound is driven by a compressed air jet flicking alternately in and out of the pipe in step with the fundamental frequency. My question is whether sound waves of the higher frequency harmonic series are emitted during the intervals when the jet is outside of the...

It will be very helpful if someone suggest any articles or reading materials on this topic for detailed study.

There are lots of videos on youtube etc showing Euler's disks. Why do we hear that periodic clattering sound? If it's a uniform rolling motion we would expect a smoother sort of whirring sound. (Like a monocycle running along a tight circle, maybe). What determines the frequency of the clatter?

Homework Statement This is a problem from the Cambridge Natural Science Admissions Assesment. A student carries out an experiment to measure the speed of sound. A loudspeaker that emits sound in all directions is placed between two buildings that are 128 m apart as shown. The student and...

Is there any sensor or method that allows a 'photo' to be taken of sound from different places? Similar to an ultrasound that is used in the medical field, but can be used more like a camera. I know about Schlieren Imaging but I'm thinking more like a map of all the sounds at a moment, maybe...

In considering a sound wave (in air) incident on a wall, the transmission loss (TL) is calculated by the equation TL (dB) = 10*Log (W1/W2) where W1 = sound power incident on wall W2 = sound power transmitted through wall Based on this understanding of TL, I wish to determine the extent to...

Okay...I have a question and I am going to describe it using a scenario...Suppose there are two persons in two different but adjacent rooms. The wall in-between these rooms is 3 inches thick. There is absolutely no way for air to cross between the rooms. Now, one of the persons speaks and the...

Hello everyone, Can I seek help on the difference of ultrasonic waves and sound waves? I find it confusing.

Homework Statement Homework Equations ##f_beat=f_1-f_2## The Attempt at a Solution Why are the two different answers? Is it because the first question is asking for how often it fluctuates, and the other is actually asking for the frequency of the sound? Why is the resultant tone the...

Homework Statement the last problem on this page: Homework Equations ##v= \lambda f## The Attempt at a Solution I'm guessing I'm looking for the maximum amplitude in a overlapping wavefront diagram like this? ## v=343m/s \\f=512Hz \\343/512=\lambda=0.67m \\3/0.67=4.5m ## So 4.5 wavelengths...

2 sound waves that are mathematical polarities cancel each other out according to my audio engineering book. I thought energy cannot be destroyed, just changed. Am I wrong? What happens to the energy? Same question could be applied to matter and anti matter right?

I'm engaged in a discussion with a friend about how loud is the sound of an airplane crashing into the ground. I'm considering that the sound wave produced is roughly spheric. I need to know how much (percent) of the kinetic energy the airplane has before hitting the ground is converted into...

1. A jackhammer produces a sound of 111 dB IL. What is the sound level when 8 jackhammers are operating simultaneously? When 100 jackhammers are operating simultaneously? When 400 jackhammers are operating simultaneously?2. 1 jackhammer = 111 dBIL, 2 jackhammers = 114 dbIL, 4 jackhammers =...

Hello! I hope I'm in the right place for this questions. In short, I'm a musical instrument builder. I'm looking at placing a piece of wood above a closed resonator box. The box (also made out of wood) will have a hole in the top that is centered under the piece of wood. I know the material that...

Sound waves transmit in atmosphere as dense and thin areas of air. Is there a graph showing the highest and lowest pressure of atmosphere for sound waves of various decibels?

I have a tube light at my home which produces this sound: The sound can be heard for a long time every time the light is switched on, but it stops after about half an hour of switching on the light. What is the cause of this sound?

Hello, I've submitted 8 topics already but sadly it was all rejected, I could really use some help to look for investigatory projects about physics

We usually describe the sound as an armonic wave while studying it's frecuency or wavelength. My doubt is if that means that we consider the air an ideal gas, so that it can affect to the result as a sistematic error. Thanks!

When sea waves approach the shore they roll up and break due to different velocities of water layers formed due to the gradual change in water depth. The highest wave peaks move faster than all other layers and thus falls down. All other layers fall the same way but in a delay. this ends up with...

I observed something which I've never seen before. We left the tap open and the water stream was flowing in a particular pattern. When we placed a beaker under the water stream, the pattern disappeared. And the pattern itself was oscillating. Here's the video link. Below the the photos of the...

Okay, I have a very simple question that...Suppose we have a very wide cube(dense and hard)...We place two persons at each of its ends...One the persons strikes its surface at one end. Now this person A will hear the sound due to vibrations of that end's surface (which further vibrate the air...

Since thermal energy is the vibration of molecules and sound is too, what is the difference? And why exactly do atoms radiate different energies as a result of vibrations?

Hi, I wonder is it possible sound wave heat material that high that the material goes up in flames? Or what other type of frequency can make some materials burn?