What is Speed of sound: Definition and 271 Discussions
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At 20 °C (68 °F), the speed of sound in air is about 343 metres per second (1,235 km/h; 1,125 ft/s; 767 mph; 667 kn), or a kilometre in 2.9 s or a mile in 4.7 s. It depends strongly on temperature as well as the medium through which a sound wave is propagating. At 0°C/32°F, the speed-of-sound is 1192 km/h, 741 mph.The speed of sound in an ideal gas depends only on its temperature and composition. The speed has a weak dependence on frequency and pressure in ordinary air, deviating slightly from ideal behavior.
In colloquial speech, speed of sound refers to the speed of sound waves in air. However, the speed of sound varies from substance to substance: typically, sound travels most slowly in gases, faster in liquids, and fastest in solids. For example, while sound travels at 343 m/s in air, it travels at 1,481 m/s in water (almost 4.3 times faster) and at 5,120 m/s in iron (almost 15 times faster). In an exceptionally stiff material such as diamond, sound travels at 12,000 metres per second (39,000 ft/s),— about 35 times its speed in air and about the fastest it can travel under normal conditions.
Sound waves in solids are composed of compression waves (just as in gases and liquids), and a different type of sound wave called a shear wave, which occurs only in solids. Shear waves in solids usually travel at different speeds, as exhibited in seismology. The speed of compression waves in solids is determined by the medium's compressibility, shear modulus and density. The speed of shear waves is determined only by the solid material's shear modulus and density.
In fluid dynamics, the speed of sound in a fluid medium (gas or liquid) is used as a relative measure for the speed of an object moving through the medium. The ratio of the speed of an object to the speed of sound in the fluid is called the object's Mach number. Objects moving at speeds greater than Mach1 are said to be traveling at supersonic speeds.
I posted a question at another forum about "choked flow" where a fluid (in this case air) if flowing through a very small orifice. Apparently when the pressure difference on each side of a orifice is about 2:1 and above then the speed of the air passing through the orifice is limited to the...
Homework Statement
The problem is you drop a coin into a well then 3 second later you hear the splash. With this information find out the height of the well.
Assume 343 m/s is the speed of sound and neglect any effects due to air resistance.
g = acceleration due to gravity = 9.8 m/s^2...
Homework Statement
A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 5.1 s later. If the speed of sound is 340 m/s, how high is the cliff?
Homework Equations
d=v/t(didnt work)
The Attempt at a Solution
My first attempt at this problem was to try...
This is turning out to be difficult for me, and I haven't even reached the part where he explains the theory of relativity itself :(
"Let us suppose that the shot is fired from the guard's-van, and the echo comes from a screen on the engine. We will suppose the distance from the guard's-van...
A 190 Hz sound traveling in fresh water has speed of?
I'm not sure which equations to use, or where to start. I tried wavelength = V/f , with V being constant, 1493 m/sAny help would be greatly appreciated!
Homework Statement
Consider the following statements made regarding the speed of sound in air,
(A) Speed increases with the increase of pressure when the temperature is kept constant
(B) speed increases with the increase of temperature and humidity
(C) speed decreaes with the increase of...
I know from my physics course that sound has a particular speed in any medium that it is traveling through, much like light. I have not learned, however, why this is so. I know that sound is simply a pressure wave traveling through air (or water or steel or whatever), but it doesn't seem...
Homework Statement
"A hammer taps on the end of a 4.17 m long metal bar at room temperature. A microphone at the other end of the bar picks up two pulses of sound, one that travels through the metal and one that travels through the air. The pulses are separated in time by 6.64 ms. What is the...
Homework Statement
In a resonance tube, using a tuning fork of frequency 325 Hz,the first two resonance lengths are observed at 25.4cm and 77.4cm.The speed of sound in air is
1. 318m/s 2. 338m/s 3.358m/s 4.378m/s 5. 368m/s
Homework Equations
v=f*lambda
The Attempt at a...
Homework Statement
Stan and Ollie are standing next to a train track. Stan puts his ear to the steel track to hear the train coming. He hears the sound of the train whistle through the track 3.1 s before Ollie hears it through the air. How far away is the train? (Use 5,790 m/s as the speed...
**this is not a homework question**
I need to know in which substance does sound travel fastest in. I know that sound travels faster when the medium is denser, therefore solids, however I would like to go more in depth. I've heard that it is iridium or hydrogen solid, but I can't get a...
Homework Statement
the air temperature is 20 degree celcius. you are swimming underwater when you hear a boat noise. then 305s later, you hear a crash. if the speed of sound in wter is 1450m/s, how long after the crash does your friend on the dock beside oyu hear the crash?
Homework...
Please help! trying to catch up with class! topic: the speed of sound
Homework Statement
Determine the depth of water if an echo using sonar returns in 870 ms and the speed of sound in water is 5300 km/h.
Homework Equations
distance= speed * time
depth=distance/2
The Attempt at a...
Homework Statement
"A rock thrown horizontally at a large bell 50m away is heard to hit the bell 4.5 seconds later. If the speed of sound is 330m/s, what was the speed of the rock? (Disregard the effect of gravity.) [Hint: If it requires a time of t for the sound to return, then it requires...
Help with lab - "Speed of Sound in Air"
Homework Statement
https://www.learningpoint.org/courses/1/C37230/content/_259415_1/Lab%20-%20Speed%20of%20Sound%20in%20Air_1.pdf?bsession=2880270&bsession_str=session_id=2880270,user_id_pk1=7284,user_id_sos_id_pk2=1,one_time_token=
Problem #1...
1. The problem statement
Hi all,
My AS physics coursework is comming up and I'm starting to plan. I will be measurng the speed of sound in air...lots and lots of times as I will then have to speculate as to how accurate my readings are.
How would you do it if it was you?
The...
So my friend in a general physics class did an experiment testing the speed of sound by snapping their fingers and having it bounce through a tube open and another that is closed. They measured a faster speed in the open tube and I am at a loss why. Did they do the measurements wrong possibly...
Please help me solving this homework!
1. List three reasons why knowing the speed of sound is important to your life?
2. From at least three sources, gather information on how you can measure the speed of sound. then, describe the methods that are available to you. Information can be...
Speed of sound at...
Homework Statement
find the values of the speed of sound in air at 30 degree.. Young modulus of cu=11 X 10^10 N/m^2 ,Bulk modulus of water=2.2 X 10^9 N/m^2 , density,p of copper=8.9 X 10^3 Kg/m^3 , density of water=1.0 X 10^3 kg/m^3
Homework Equations
do not...
I am currently enrolled in a driver / operator class for my fire department and a statement that was written in our textbooks has been bothering me. " If a fire apparatus is traveling at 40 miles per hour the siren can be heard at a distance of 300ft. However, if a fire apparatus is traveling at...
In a mixture of argon (atomic mass = 39.9 u) and neon (atomic mass = 20.2 u), the speed of sound is 363 m/s at 300K. Assume that both monatomic gases behave as ideal gases. Find the percentage of the atoms that are argon and the percentage that are neon.
I found the solution (in the...
[b]1. A soccer player kicks a rock horizontally off a 40.0 m high cliff into a pool of water. If the player hears the sound of the splash 3.00 s later, what was the initial speed given to the rock? Assume that the speed of sound in air is 343 m/s.
Homework Equations
The Attempt at a...
Homework Statement
A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 4.7 s later. If the speed of sound is 340 m/s, how high is the cliff?Homework Equations
d=vit+.5at^2
vf^2=vi^2 +2ad
vf=vi+at
The Attempt at a Solution
so, i don't know how to have both the...
Hello everyone :smile:
I'm learning sound at the moment and I would really appreciate if you people can fine tune my knowledge.
My understanding of the sound wave. An object is vibrating
The forward motion of the object: The particles closer are compressed and they push the adjacent particles...
suppose air is flowing throught the nozzle
with the inlet conditions
static pressure = .2 MPa
static temperature = 350 K
velocty of air at the inlet = 150 m/s
speed of sound for ideal gas is given by c = sqrt (k * R * T)
suppose if i want to calculate the speed of sound at the inlet...
Homework Statement
A metal tube with length 931m is hit with a hammer. On the other end two sounds with time delay of 2.5 seconds can be heard. What is the reason for this? What is the speed of sound in the metal?
Homework Equations
t=L/v
The Attempt at a Solution
I think the...
Two questions:
1. A sailor strikes the side of his ship just below the waterline. He hears the echo of the sound reflected from the ocean floor directly below 2.02 s later. How deep is the ocean at this point?
I assumed this used distance = speed x time. I knew that speed must equal the...
Homework Statement
does the speed of sound increase as the temperture becomes closer to absolute zero, which would make the substance more and more dense?
Homework Equations
dont think there is any
The Attempt at a Solution
really confused as, isn't it the more dense a substance...
Would it be possible for someone to check over my experiment? I have not conducted the experiment yet, but I would like to make sure I am on the right tracks.
The equation I will be using to determine the speed of sound is:
v=f\lambda
v is the speed of sound
f is the frequency and this will...
Homework Statement
The effective spring stiffness corresponding to the interatomic force for aluminum and lead. Let's assume for the moment that, very roughly, other atoms have similar values as Pb and Al. Pb has a velocity of 1200 m/s and Al has a velocity of 5000 m/s
(a) What is the...
Homework Statement
A 15.7cm long, closed-end tube, filled with air, resonates when exposed to sound waves with a frequency of 550hz. Calculate the speed of sound.
Homework Equations
V=331.4 + 0.6*Temp.C
V=wavelength*frequency
V=d/t
The Attempt at a Solution
I'm thinking I...
Homework Statement
Using a theoretical treatment including \gamma (the ratio of cp to cv), determine the speed of sound in each of these gases: argon at 273 K, methane at 165 K, nitrogen at 600 K.
Answer must be applicable to any gas at any temperature
Homework Equations
The...
Homework Statement
A source and an observer are each traveling at 0.52 times the speed of sound. The source emits sound waves at 1.2 kHz.
(a) Find the observed frequency (in kHz) if the source and observer are moving toward each other.
(b) Find the observed frequency (in Hz) if the...
Homework Statement
A stone is dropped from rest into a well. The sound of the splash is heard exactly 1.50 s later. Find the depth of the well if the air temperature is 6.0°C.
Homework Equations
i'm not sure what equation i need to use here.
i know that 6C=279.15K
v=dx/dt...
Quick Question...If a supersonic jet passes directly in front of you and you are infinitely close to the jet (there is no distance between you and the jet theoretically), would you hear the jet as it passes you or after it has already passed you?
I think you would hear it as it passes...
Speed of Sound and Mach
Homework Statement
You are hired as the physics consultant for a large movie studio. The producer is way over budget and wants to perform some special effects that will save him money. He decides to shoot the dramatic action boat chase scene with the boats going at 1/4...
Homework Statement
One cue your hearing system uses to localize a sound (i.e., to tell where a sound is coming from) is the slight difference in the arrival times of the sound at your ears. Your ears are spaced approximately 20 cm apart. Consider a sound source 5.0 m from the center of your...
This isn't really a homework problem, but I am doing a research paper on the topic 'the Speed of sound in different air velocities'.
I was just wondering is this is an appropriate topic, and whether or not I would be able to research and collect enough data for a 4000 word essay.
Any...
Can someone tell me how I find the speed of sound in air?
If I plot a graph of frequency against length would I be right in saying that I can find the speed of sound by finding where the two points on the graph intersect and multiplying by 2, so that
v = 2 * Lf
In my sophomore mechatronics class, the professor mentioned that when we design rotating devices (i.e. a fan), we should make sure the outside edges don't move faster than the speed of sound. I always wanted to ask him why but never got a chance. Since then the question has been bothering me and...
Alright we did a lab using the speed of sound we were suppose to able to calculate the temperature outside.
v = 332 +0.6T
So this is what we did, one person hit two blocks together twenty times at an equal pace. The timers start when the person first hits the block together and stops when...
Homework Statement
A man strikes a long aluminum rod at one end. Another man, at the other end with his ear close to the rod, hears the sound of the blow twice (once through the air and once through the rod), with a 332ms interval between them. How long is rod?
Homework Equations...
Hello, I tried solving this but to no avail.
Maybe someone could help me figure out the answer, thanks.
A rock is dropped from a sea cliff and the sound is heard striking the ocean 3.0s later. If the speed of sound is 330 m/s. How high is the cliff?
Thanks.
:wink:
I've already tried about...
Homework Statement
The speed of sound in air is proportional to the square root of the temperature in kelvin. A flute player begins playing with the temperature of air in the tube at 288 K. The speed of sound at this temperature is 340 m s–1. After a few minutes playing the air temperature in...
i'm doing extra problems in my textbook but one of them baffles me...
a hiker shouts toward a vertical cliff 685 m away. the echo is heard 4 s later
what is the speed of sound of the hiker's voice in air?
i know to calculate this you do velocity=distance/time.
and i did velocity=685/4...
Today i did a simple expirement to calculate the speed of sound by placing someone 180 m away from me and telling the clap two wooden blocks. I timed the time it took between me seeing the blocks hit each other and when i heard the sound of the two blocks. Now in order for this to be as acurate...
Dolphins emit ultrasonic waves with a frequency as high as 5.5 x 10^5Hz. What is the wavelength of such a wave in seawater at 25°C?
i know how to solve this one, all i need is the speed of sound waves in seawater at 25 degrees Celsius. My teacher gave us the speed in water at 20C which =...