Why is there are sonic boom when planes make the sound barrier?
A sonic boom is the audible component of a shock wave in air. The term is commonly used to refer to the air shocks caused by the supersonic flight of military aircraft or passenger transports such as Concorde (Mach 2.03, no longer flying) and the Space Shuttle (Mach 27, has only flown once since the 2003 crash). Sonic booms generate enormous amounts of sound energy, sounding much like an explosion; typically the shock front may approach 167 megawatts per square meter, and may exceed 200 decibels.
When an aircraft is near the sound barrier, an unusual cloud sometimes forms in its wake. A Prandtl-Glauert Singularity results from a drop in pressure, because of shock wave formation. This pressure change causes a sharp drop in temperature, which in humid conditions leads the water vapor in the air to condense into droplets and form the cloud
No it is not correct. A sonic boom is a sound made by an object moving faster than the speed of sound. If your fingers did this they would be broken by the force of the acceleration to get to such a speed in such a small distance. The tip of a whip moves faster than the speed of sound.
All you are hearing is the air forced out from the groves in your hand as your other finger compresses them. The sound from it travels at the speed of sound, but is not a sonic boom.
Sonic boom is an impulsive noise similar to thunder. It is caused by an object moving faster than sound, about 750 miles per hour at sea level. An aircraft traveling through the atmosphere continuously produces air-pressure waves similar to the water waves caused by a ship's bow.
When the aircraft exceeds the speed of sound, these pressure waves combine and form shock waves which travel forward from the generation or "release" point.
How long does it take for a sonic boom to dissipate?
Couple of points in answering your question:
1. A sonic boom happens whenver an object exceeds the speed of sound - like a bullet being fired from a gun. It doesn't have to happen high in the atmosphere. The Concorde normally crossed the sonic threshold high by regulations, not because of its capabilities.
2. Think of a sonic boom as the same as a clap of thunder. If you define "causing a problem" as being heard by humans on the ground, that's one thing - if you define it as blowing out all the windows in your house, that's another thing.
3. Aircraft flying over the continental United States at any altitude are forbidden by FAA regulations to exceed the speed of sound - except for designated military operations. Similarly, the Europeans have the same regulation, so the Concorde was not allowed to go "supersonic" until it was out over the ocean.
4. I'd imagine that a Concorde going supersonic at 30,000 feet would be heard on the ground, but without causing any damage from the sonic boom. Going supersonic at 60,000 feet would probably not generate much noise, and no damage, on the ground. Somewhere less than 5-10,000 feet and things start to get interesting. I read a report of an airshow where some of the fighters were doing low passes down the runway really fast and one guy got carried away and went supersonic at about 100 feet. He blew out all the windows in the tower and in the side of the terminal that faced the runway. So there's a situation that caused "problems" with the ground-based population.
5. Having flown on the Concorde, I can tell you that there was absolutely no sensation whatever when the aircraft went supersonic. Just like sitting in your living room.
how is a sonic boom created in physics reference please?
A sonic boom is the sound associated with the shock waves created by an object traveling through the air faster than the speed of sound.
When an object passes through the air it creates a series of pressure waves in front of it and behind it. These waves will travel at the speed of sound.
As the speed of the object increases, the waves are compressed together, because they cannot get out of the way of each other, eventually merging into a single shock wave: What we call the "Sonic Boom."
A sonic boom is the audible component of a shock wave in air. The term is commonly used to refer to the air shocks caused by the supersonic flight of military aircraft or passenger transports such as Concorde (Mach 2.2, no longer flying) and the Space Shuttle (Mach 27). Sonic booms generate enormous amounts of sound energy, sounding much like an explosion; typically the shock front may approach 100 megawatts per square meter, and may exceed 200 decibels.
10 log (100 x 10^(6)/ 10^(-12)) = 200 dB
This may vary slightly depending on the sound energy but 200 dB is considered the normal, this is at the source of course.
Just to make it abit more interesting for you, if it happened at 30,000 feet above, your hear a decibel level of:
30,000 ft = 9146 m (approx)
200 - (20log(9146) + 11) = 109.77 dB
A burglar alarm is approx 110 dB
Why was there a sonic boom from the meteor that hit russia?
Any object going faster than the speed of sound produces a sonic boom. It is caused by the air not being able to get out of the way fast enough (the "speed of sound" exists because of the size of air molecules and their ability to bounce off each other as energy travel through air, as in "sound").
The object does not have to explode to cause a sonic boom.
The space shuttle, when it got low enough, was always heard to produce a sonic boom (a double-boom) as it passed over towns in Florida, until it has slowed down enough to go slower than the speed of sound (a few minutes before landing).
Sonic booms can be quite annoying and can cause damage (the amount of energy depends on the speed, the mass of the object and its shape -- how much air must get out of the way and how fast must it get out of the way).
This is why the supersonic passenger jet Concorde was not allowed to travel at supersonic speeds when over inhabited land. And it was a tiny object, streamlined to allow a smoother flow of air around it.
The Concorde was over 100 tonnes but "only" flew at twice the speed of sound ( 0.6 km/s ). The Russian bolide was less massive but came in at around 15 km/s (I read 18 km/s somewhere), which is almost 50 times the speed of sound, and was shaped... err... like a rock.
In addition, when the bolide broke up, it was still going above the speed of sound, so that you suddenly get "a bunch of objects" moving faster than the speed of sound, instead of just one. This gives you compression waves one on top of the other (these compresison waves can only move at the speed of sound, so they cannot pass each other). The "overpressure" (this is what causes damage to large areas like windows and walls) was the addition of all the sonic booms (as they all hit at exactly the same time).
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Which is louder and more devastating a sonic boom from a jet?
Both thunder and sonic booms are variations on the same theme. Both are sound waves that originate as shock waves. In the case of thunder, the rapid expansion of air in the channel of a lightning stroke produces a shock wave that rapidly degenerates into a sound wave, producing thunder. In the case of sonic booms, an airplane flying at supersonic speed generates a pair of shock waves that also degenerate into sound waves.
Both sonic booms and thunder are harmless to human beings, except perhaps for the noise at close range. Thunder is generally held to be harmless to structures, at least at reasonable distances from lightning strikes. Sonic booms supposedly can damage structures, although actual evidence for this is debatable. Thunder is typically much, much louder than sonic booms.
Does a pilot that breaks the sound barrier hear the sonic boom?
No, a sonic boom is actually a very rapid change in ir pressure that travels in a cone shaped wave. This is why we call it a shockwave. At any point on the aircraft during thr flight, the air pressure is more or less unchanging. At least, it doesn't change rapidly enough for the pilot to hear the boom. Think of it as the pilot riding just behind the sonic boom. He's travelling with it, so it never passes over him. Anyone outside being passed will hear it because the wave actually moves over them. Another way of imagining it is a swimmer. Because he's making the wave with his head and shoulders, as he moves through the water, he doesn't feel the wave. It's moving out away from him. Anybody nearby will feel it pass, though.
how are sonic booms present in our everyday lives? :)?
They come from an object breaking the sound barrier for the medium it's in. The "bow shock" builds up, and when the sound waves compress very closely and then get the physical object passing through that compressed area, the resulting collapse of turbulence produces a loud noise.
One of the most common examples is the crack of a bullwhip: the tip of the whip actually breaks the sound barrier.
We also get a pair of sonic booms when a Space Shuttle lands, as the process happens in reverse: the craft slows down below mach 1, with the same effect. We get one boom each from the front of the craft (traveling through normal air) and the tail fin (traveling through a slightly rarefied stream with a greater speed of sound).
Sonic booms are not any more dangerous to us than other loud noises: the shock wave rattles dishes and has been known to break windows when a fast jet would pass mach 1 low over an urban area.
I don't know how they were "discovered", although I would think that it was some time in the X-15 period, when the USA was first building supersonic craft. Try the link below or other sources on sonic booms.
Short answer, an N-wave forms as all of the individual shocks from nose, cockpit, wings, engine inlet, etc coalesce into a single shock wave far from the aircraft. The N wave is a sharp rise in pressure followed by a sharp drop in pressure. This is heard as a "boom."
If you have an airplane on the ground, the sound waves coming from it go at the same speed in all directions. If the plane is moving at the speed of sound then it is exactly "keeping up" with the sound waves in front of it. If the plane moves faster than the speed of sound then it is outrunning the sound it makes. The result is a mach cone starting at the tip of the nose. In front of the cone you wouldn't hear the plane, behind it you would, and the surface of the cone would be the shock wave. Look up the Doppler effect if you want to see some good graphics.
There have also been a lot of cool programs/experiments to minimize sonic booms. Look up the Shaped Sonic Boom Demonstrator (SSBD) for an example.
soundwaves and sonic booms in an imaginary GIANT world?
sonic booms are caused when an object in a fluid moves faster than the speed of sound in the fluid
V sound is related to pressure density and temperature ( I forget the equation)
G the acceleration of gravity at the surface depends on the total mass AND the distance to the center of mass ( geometric center for a sphere)
It is very hard to scale directly since size goes as the first power of L dimension
Area of structure goes as L x L and mass goes as volume L x L xL
(an elephant is NOT just a big mouse)
Keep thinking that is how science works
The sonic boom is created at the moment the object is travelling exactly at the speed of sound, not when it is slower and also not when it is faster. What happens at that moment is sound waves in the direction of travel are moving at the same speed as the object itself, so they "pile up" in front of it and a large amount of energy gets packed into a small amount of propagating space. That concentrated energy continues travelling in other directions as well, eventually hitting the ground all at once and producing the sudden boom that we hear.
Because the atmosphere is rotating with it - or do you get 420 m/s winds at your location? ;)
Sonic booms happen when you have supersonic flow of a gas around an object, so shock waves form, you can actually even shape objects in a way, that they can't produce a sonic boom, but such a shape is usually useless for all applications.
Also, you wouldn't get sonic booms if you are standing on Earth and you have supersonic wind speeds - the rapid change in the airflow, which you perceive as sonic boom, would not be audible (just like you can't hear the sonic boom inside a supersonic aircraft). Even if the shock waves would impact on you - you would get battered by the supersonic wind even more, but not hear it.
Sonic Boom is music from Sonic CD (USA) english version.
Sonic Boom can be from Guile by Street Fighter 2.
Sonic Boom can be an explosive sound caused by the shock wave preceding an aircraft traveling at or above the speed of sound.
Is it possible for other planets to have sonic booms on them?
The term sonic boom is commonly used to refer to the shocks caused by the supersonic flight of an aircraft. Sonic booms generate enormous amounts of sound energy, sounding a lot like an explosion.
Thunder is a type of natural sonic boom, created by the rapid heating and expansion of air in a lightning discharge.
Gaseous planets like Jupiter and Saturn have lightning and so they already have sonic booms. Any planet with an atmosphere could sustain a sonic boom.
Though the above guys gave you some nice information, none of them actually answered the question correctly.
When an object is travelling faster than the relative speed of sound slows down to below the speed of sound, that transition creates what we call a "sonic boom". Note that it doesn't work the other way.
A meteor is typically travelling 30kps or about 1000000kph. This is way faster than the speed of sound where ever you are in the atmosphere, and will very very very unlikely slow down past that transition point before impact. For that to happen, the size of the remaining meteor would be TINY and so the magnitude of that sonic boom created would be insignificant anyway - nothing close to blowing out any windows.
Hence ... Meteors don't really create sonic booms. They can be very loud though :).
Let me give you a nice example to clarify: http://www.youtube.com/watch?v=QX04ySm4TTk
In this vid there are two separate sounds being made. The roar of the jet's engines, and the sonic booms as the jet dances around that transition region (0.85
The shock wave forms a cone of pressurized air molecules which move outward and rearward in all directions and extend to the ground. As the cone spreads across the landscape along the flight path, they create a continuous sonic boom along the full width of the cone's base. The sharp release of pressure, after the buildup by the shock wave, is heard as the sonic boom.
The change in air pressure associated with a sonic boom is only a few pounds per square foot -- about the same pressure change experienced riding an elevator down two or three floors. It is the rate of change, the sudden onset of the pressure change, that makes the sonic boom audible.
All aircraft generate two cones, at the nose and at the tail. They are usually of similar strength and the time interval between the two as they reach the ground is primarily dependent on the size of the aircraft and its altitude. Most people on the ground cannot distinguish between the two and they are usually heard as a single sonic boom. Sonic booms created by vehicles the size and mass of the space shuttle are very distinguishable and two distinct booms are easily heard.
As an object moves through the air, it creates a series of pressure waves in front of it and behind it, similar to the bow and stern waves created by a boat. These waves travel at the speed of sound, and as the speed of the aircraft increases the waves are forced together or 'compressed' because they cannot "get out of the way" of each other, eventually merging into a single shock wave at the speed of sound. This critical speed is known as Mach 1 and is approximately 1,225 kilometers per hour (761 mph) at sea level.
In smooth flight, the shock wave starts at the nose of the aircraft and ends at the tail. There is a sudden rise in pressure at the nose, decreasing steadily to a negative pressure at the tail, where it suddenly returns to normal. The "boom" is experienced when there is a sudden rise in pressure, so the wave causes two booms, one when the initial pressure rise from the nose hits, and another when the tail passes and the pressure suddenly returns to normal. This leads to a distinctive "double boom" from supersonic aircraft. Since the boom is being generated continually as long as the aircraft is supersonic, it traces out a path on the ground following the aircraft's flight path, known as the boom carpet.
In short: Air being pressurized and depressureized very, very (very) fast. A really big version of what happens when you open a glass bottle of Coke.
Hope that helps,
All of these aircraft like the DC-10, 707, DC-8 and so on, are strong enough to fly inverted. The 707, on it's original demo flight, actually did a roll. I suspect the pilot got into trouble for that, but it did make the point that, big as they are, they are strong and manoeuvrable..
However, I have never heard of a large aircraft like this actually going supersonic. Although they are slippery, there is too much frontal area. It needs to much power to drive it through. Even in a dive, there is too much resistance, even at altitude. If you take a barn door up to 50000 feet and drop it, and you go and sit on it on the way down, I think you will not make a sonic boom. You might make a bit of a "thump" at the bottom end of the drop.
I have three answers. I will try to follow the KISS principle (Keep It Simple, Stupid). No, I am not calling you Stupid.
1. A shock wave is where there is the highest intensity in a compression wave. Shock waves are ALWAYS compression or longitudinal waves. They can be found in solids, liquids and gases. In a solid, for example, if you have a steel rod, and hit one end with a hammer, a shock wave travels down the rod to the other end.
2. A sonic boom is a type of shock wave in a gas (the atmosphere) where an object which is GENERATING NOISE (generally an aeroplane) is travelling at the same speed as the sound itself, so all the noise travelling in the direction the object is travelling is being componded together to make one ENORMOUS noise, called the sonic boom.
3. I think the answer to Question 3 is given in 2. In summary, a sonic boom is ONE type of shock wave.
The strongest sonic boom recorded was 144 lbs per square foot by a fighter flying just above the speed of sound at 100 ft. off the ground. A more realistic force would be around 21 lbs per square foot for an aircraft flying at altitude.
An average sonic boom will produce 212 decibels when the listening device is near the aircraft.
Sonic booms have the ability to shatter glass and affect crop growth, this is why Concordes did not go supersonic until over the ocean.
Any supersonic aircraft (or other body) moving through air will generate what is known as a Mach cone.
The motion of the body through the air creates a pressure disturbance that spreads outwards with the speed of sound and forms the cone. The cone trails behind the body much as a wake trails behind a ship.
The sharp pressure disturbance at the surface of the cone is heard as a large bang whenever the cone sweeps over the ear. This is the sonic boom.
When the concorde SST was flying the noise level of the sonic boom reached the pain threshold even with the aircraft 20 km away, so it was restricted to sub sonic speeds when flying over urban areas.
It is the shock wave created when something travels faster than the speed of sound, the "crack" of a bull whip or the "boom" from a jet fighter are examples. The sonic boom from aircraft have been known to rattle dishes and windows, startling civilians and have been mistaken for earthquakes. Unless there is some critical need, super-sonic flight is prohibited over inhabited areas. Super-sonic flight is usually allowed over large bodies of water, oceans or lakes.
When something travels faster than the speed of sound, you get a sonic boom.
When smething travels faster than the speed of light, (in a clear media) you get Cherenkov light. (blue glow)
Actually, when a jet is traveling at exactly the speed of sound, there is no sonic boom. Once it breaks the sound barrier, it emits a continuous sonic boom. It only sounds like one boom because the plane is only going by you at one point. The volume of the sonic boom is determined by the size of the object: big objects move more air, so it will be louder, and vice versa. When it goes faster, it does not make a louder boom.
I know an engineer will come along and give you the best answer, but from what I know Air can be compressed. The Space Shuttle de-orbits the earth at around 17,000 miles per hour, I think. When it slows enough to re-enter the atmosphere, it begins hitting the air and this happens so fast that air begins to pile up in front of the nose of the Space Shuttle faster than it can go around the space shuttle. The air is compressed for a split second before it goes around the space shuttle. Eventually the air pressure in front of the space shuttle is more than can be piled on, and it is then forced back around and behind the space shuttle...just like the wake of a boat in water. Water is a fluid, and air is also a fluid. The sonic boom happens when the compressed air UN-compresses suddenly when it goes behind the fuselage and the wings of the space shuttle...or any super-sonic aircraft. It's like when a balloon pops. The air in a balloon is compessed and when the air is released suddenly, it does so with a bang. The pressure is released so suddenly that it happens with a bang...and that is the sonic boom. I think it is the air molocules actually slapping together during the collapsing air pressure. They say that if you listen closely that you can actually hear two sonic booms because there are actually two shock waves on a super sonic aircraft. One from the nose of the aircraft and one from the tail which sticks so high up into the air stream. I think the speed of sound is around 750 miles per hour. That is where sonic booms are first heard. The space shuttle is going over 10,000 miles per hour when it re-enters. That is also why you don't hear a sonic boom until the aircraft is well past where you are standing. Sound only travels at 1100 feet per second through the air. The aircraft is going much faster than that. That's rocket science. Hopefully a rocket scientist will come in and answer this. Let's see, 750 miles per hour is almost 4 million feet per hour or 1100 feet per second. While in orbit, the space shuttle travels around the globe in around an hour. That's gotta be more than 23,000 miles per hour. That's 30 times the speed of sound. Mach 30 Wow!
It's just the miners. They use a lot of dynamite. I think too much. They're definitely overdoing it. they just want the diamonds berried underneath your house. It's no bid deal.
No but seriously I have no idea. It could be seismic activity. It could be sonic booms, or it could be military explosion tests. Usually with jets breaking the speed of sound, they fly high enough so it doesn't disturb anyone. And this also depends on how often this occurs. If it's like once a week it's probably not a small earthquake. If you're hearing huge booms I'd just say Sonic booms. You should definitely check with that military base and see what's up. Ask them if they do supersonic tests and if they do ask them if you'd be able to hear it or if the vibration could reach you.
But I have to be honest, right around that area, there are tons of caves and tunnels underground. I wouldn't be surprised if they're dynamite explosions. It would be interesting to find out they're blowing up rock 300 feet below your house!!
No. No second sonic boom. The boom occurs when the source of the sound, the plane, is traveling faster than the sound waves propagate through the medium, which is air. Increasing speed just leaves the sound farther behind. The boom radiates from the plane at the speed of sound, about 750-770 mph, give or take, depending on altitude, temp, and other variables. The faster the plane goes, the more stretched out the boom seems. At an approximate 1000 fps, the boom of a plane 10,000 feet above will arrive ten seconds after the plane flies over. If the plane is going 1000 fps, it will be 10,000 feet farther away when the boom reaches ground. At Mach 2, it will be 20,000 feet away, at Mach 3, 30,000 feet, etc. But, still, only one boom.
Inside the hull of a 700 mph plane, the air is also traveling 700 mph. Throwing the ball at 65 mph will not cause a sonic boom. Einstein's speed of light stuff does not work when the medium that conveys the energy, that being air, is also moving.
It wouldn't cause a sonic boom but it sure would rip you arm off.
The sonic boom is not a single event, by the way. It is simply the shock wave passing over an external observer. It does not happen while you are passing the sound barrier but it happens all the time while you are flying faster than sound.
The term Sonic boom is commonly used to refer to the shocks caused by the supersonic flight of military aircraft or passenger transports such as Concorde (Mach 2.03, no longer in service) and the Space Shuttle (up to Mach 27). Sonic booms generate enormous amounts of sound energy, sounding much like an explosion; typically the shock front may approach 167 megawatts per square meter, and may exceed 200 decibels. Thunder is a type of natural sonic boom, created by the rapid heating and expansion of air.
A sonic boom is a shock wave produced by an aircraft as it moves through the air at a speed greater than the speed of sound. Typically there are two shock waves, one produced at the front of the aircraft, one at the rear.
The people inside the aircraft don't hear a sonic boom because the shock wave remains in one place in relation to them. It never moves across or past them, so they don't hear it. People on the ground hear the sonic boom because the shock wave passes them as the aircraft moves. Actually, what people hear is a loud sound wave, since the shock wave slows to the speed of sound as it expands outwards from the aircraft.
It's like a speedboat traveling across a lake. The people near the boat as it passes will feel the wake from the boat, but the people in the speedboat itself won't, because they are creating the wake and it doesn't move in relation to them.
what is the connection between shock waves and sonic boom?
A sonic boom is a shock wave, but a shock wave is not a sonic boom.
Shock wave is the generic term for any compression, longitudinal wave that comes from the rapid compression of a gas: like when an air plane slices into the air in front of it or an explosion expands and compresses the air around it.
A sonic boom is a shock wave coming from an airplane that is flying faster than sound so the air molecules are pushed out of the way faster than they would like to go. So they pile up in a highly dense volume of space off the leading edges of the plane. When they can finally get back to the speed of sound, after the plane passes through, they snap back and make that boom we all hear in trail of a faster than sound aircraft going overhead.
As it turns out, the speed of sound and sonic booms are not as straight-forward as one might think. Firstly, a sonic boom is not a single event that happens only at the moment the sound barrier is broken. The event continues as long as the vehicle (or person in a suit) is traveling faster than the speed of sound, and is heard in a specific area below the path of the vehicle. But, here's the kicker. In order for a sonic boom to be heard on the ground, the vehicle must be traveling faster, relative to the ground, than the speed of sound on the ground. Since Baumgartner was traveling faster than the speed of sound VERTICALLY, and his horizontal speed relative to the ground was only a few miles per hour at best, the sonic boom he created would not have been heard on the ground at all. The only way his boom could have been heard was if there had somehow been a person in the atmosphere as he rocketed past them, and that was, of course, not the case. So, yes, he caused a sonic boom, but it is very unlikely that anyone heard it.
Just another note. It was stated in an earlier post that sound travels faster in a gas (air) than it does in water. Actually, the more dense a material is, the faster sound travels through it, including water.
What would be a sonic boom caused by a human-sized object be like?
Sonic booms are much the same no matter what causes them. The only things that change are the strength of the boom, which is related mostly to the size of the object and its shape, and the distribution of multiple shock waves. Usually there will be two, one produced by the front of the object, and another produced by the back (where air merges against behind the object). A long, thin object may produce two very distinct booms, whereas sphere or similar object of small size might produce shock waves so close together that they are heard as one boom.
The altitude also matters. At high altitudes, there's not much air, and the shock wave will be quite weak. At sea level, the shock wave will be substantial. Speed is a factor, too, of course.
Ultimately all sonic booms soften and merge into a sound like rolling thunder at sufficient distance. That's because rolling thunder IS a sonic boom, caused by the expansion of air produced by a lightning stroke.
SHORT ANSWER: A sonic boom happens whenever some object travels faster than the speed of sound in whatever medium it's traveling through. The sound waves emitted by such an object pile up and form a high-pressure cone, which sounds like a loud crack or boom.
MORE DETAILS: Sound is a series of pressure waves. In order to hear an object, it has to be vibrating against some medium (usually air) causing waves of high and low pressure to spread outward from the vibrating object. Your eardrums detect these pressure oscillations, and your brain interprets them as sound.
Let's consider a jet plane that is stationary on the runway. It's giving off sound, and the sound waves are spreading out from the jet in concentric spheres traveling at roughly 340 meters per second. (That value is actually an estimate; the speed of sound in air varies widely due to temperature, density, etc)
If you're standing near the stationary jet, the sound is rushing past you at 340 m/s, and your eardrums are being assaulted by rapid changes in pressure - high-low-high-low-high-low - possibly hundreds or thousands of times a second.
Now let's say that the jet is moving forward at half the speed of sound: 170 m/s. It's still emitting sound waves that travel outward at 340 m/s, but they're no longer concentric. The waves in front of the jet are squeezed together and the waves behind the jet are stretched out. That's because in the time between two waves, the jet has moved forward slightly. Remember that each wave is a high pressure band followed by a low pressure band.
When the jet approaches the speed of sound, the waves in front of him are REALLY squeezed together, and he's right there behind them. If the pilot actually breaks the sound barrier, he'll be traveling faster than his own waves. The "fronts" of his sound waves will form a highly-compact high-pressure cone trailing behind the jet. Immediately inside this cone will be a very low-pressure region.
The loudness of a sound depends on its amplitude, which is related to the difference in pressure between the high- and low-pressure bands. In a sonic boom, this pressure difference is IMMENSE! When this sound cone reaches our ears, it sounds like an incredibly loud bang: the result of receiving MANY of the jet's sound waves at once, followed by a rapid drop in pressure.
I hope that helps. Good luck!
Depends on the distance the jet is from you when it passes. A sonic boom is nothing more than the pressure of the air that the jet displaces being pushed into the air next to it faster than that air can get out of the way. The resulting wave travels at the speed of sound (770mph or 1129 fps). So for every 1129 feet of altitude of the jet, there will be a 1 second delay in the boom. At most air shows, jets operating at those speeds are several thousand feet in the air and you would be a few hundred yards away making the total distance be even longer than their altitude, so you could expect a few seconds delay between the jet passing and the boom.
p.s. - There are actually 2 sonic booms. One from the air being pushed out of the way by the nose and wings of the jet and a second smaller one of the air being sucked back into the space behind the jet as it passes.
A sonic boom occurs when the source of a sound moves faster than the speed of sound in that medium. A shockwave is formed containing a short but intense burst of acoustic energy - the boom.
Creating a sonic boom in air is somewhat difficult, although you can use a whip effect on a cord to create a sonic boom (because the energy of the whipping motion gets concentrated into the very tip and causes it to exceed the speed of sound). However, this sonic boom is invisible, and very short.
You could also create a shockwave in a viscous liquid like water. The speeds could be much slower than a sonic boom, and visible.
A typical question involving sonic booms is Why are there two booms when the Space Shuttle goes by?
Sonic Boom-ending theme U.S.A. version
If you're strong, you can fly
You can reach the other side of the rainbow.
It's your right, take a chance
'cause there's no circumstance
that you can't handle (When you use your mind)
Mr. Bad's got it good
But, this ain't his neighborhood
he's taking over oh, no
Time is now, he can't hide
Find the power deep inside and make it happen.
Sonic Boom, Sonic Boom
Trouble makes you running faster
Sonic Boom, Sonic Boom
Save the planet from disaster
Sonic Boom, Sonic Boom
Spinning through a world in motion
Sonic Boom, Sonic Boom
TAKE IT ALL THE WAY!
It's your move, break it out
That's what life's all about
It's your adventure
To the dark, to the light
It's a Super Sonic flight
Gotta keep it going!
Sonic Boom, Sonic Boom
Sonic Boom, Sonic Boom
Sonic CD ((Japan/Europe version))- Cosmic Eternity ending theme
In the end, Who's on your side
Who can you trust, in the middle of the night
here will you be, if ya can't find you
There's no-place to go, Nothing to do
If ya gotta do something, gotta do something
Believe in yourself - Yourself - Yourself - HEY !
Extraordinary thing can happen
if you believe in yourself
You've got to have some faith in yourself,
if you want respect from your friends
(Believe in what you want to do)
Don't re-arrange - No need to change
Stay like you are - Keep it all the same
But as you move along in your life
Keep and open mind and don't forget
That if ya gotta do something, gotta do something
Believe in yourself - Yourself - Yourself - HEY !
Extraordinary thing can happen
if you believe in yourself
You've got to have some faith in yourself,
if you want respect from your friends
(Believe in what you want to do)
When you feel tight, Look at yourself
Inside your heart you will find
a special place to unwind
When you feel right, Look at yourself
Inside your mind you will see, Cosmic Eternity
When you feel tight, Look at yourself
Inside your heart you will find
a special place to unwind
When you feel right, Look at yourself
Inside your mind you will see, Cosmic Eternity
minimum speed at which a plane must fly to produce sonic boom?
sonic booms are created when an object passes the speed of sound (*either* accelerating OR decelerating) ... so a plane actually makes two ... one as it crosses mach 1 and another as it comes back. (nothing happens when you cross mach 2 ... that's not where the event boundary is.)
the speed of sound is dependent on MANY things, not the least of which are altitude, humidity and temperature (which affects air density).
so, to answer your question ... a plane flying right at ANY of those speeds will not create a sonic boom (not even 350 m/s) ... to create the boom, you have to *cross* the barrier.
assuming your definition of 350 m/s, you'll produce a boom at (a) or (b) if you were traveling faster than 350 m/s, then slowed down. you'll create one at 700 m/s if you were traveling slower than 350 m/s and sped up. you may or may not create one (or multiples) at 350.
HOWEVER, some stealth aircraft are rumored to *never* create booms, regardless of speed increases/decreases. (almost certainly true.) which means the correct answer in those cases would be (e) "never."
the sonic boom from faster-then-sound aircraft is caused by a pressure wave at the nose of the plane. It actually forms a cone, ( or nearly conical pressure wave) that seems to make an explosive sound as it passes listeners.
You might be interested to know that that the sound of a whip cracking is actually a tiny sonic boom. As the tip of the whip reverses direction its angular momentum more than doubles and goes faster than the speed of sound... CRACK!
Now to understand your question, if you could get a blade to cut through the air faster than the speed of sound, yes, it might make a boom, but that boom is not perceived that way because it would be stationary.
Also, the way a blade moves, (in a circle) creates vortexes, but not a single sudden pressure wave.
The whip cracks because it makes a sudden jump to supersonic speed, relative to the listener's ear.
The plane makes a sonic boom because the pressure wave is moving past the listener.
A blade will create vortexes that prevent a sudden change in pressure that we associate with "sonic boom."
One last point, it might be possible to get an irregular, non-symmetrical blade to create a sonic boom, but it would require a tremendous amount of torque to do it. The machine would be very loud already, and it would be dangerous! There would not be any appreciable effects on nearby buildings, unless parts flew off, and that would be likely. Such an imbalanced machine would probably vibrate itself apart.
If you would like to actually "see" and hear sonic booms in action, just go to Google video and search, "Sonic Boom, F14" There are numerous videos of this phenomenon where you can actually see the pressure cone over water. It really is impressive!
Sonic boom is a common name for the loud noise that is created by the 'shock wave' produced by the air-plane that is traveling at speeds greater than that of sound . These speeds are called supersonic speeds, hence this phenomena is sometimes called the supersonic boom.
Normally, for a plane that is going at subsonic speeds (lower than that of sound), the sound of the plane is radiated in all directions. However, the individual sound wavelets are compressed at the front of the plane and further spread at the back of the plane because of the forward speed of the plane. This effect is known as the Doppler effect and accounts for the change of the 'pitch' of the plane's sound as it passes us. When the plane is approaching us it's sound has a higher pitch than if it is going away from us.
Now, if the plane is traveling at the supersonic speeds (greater than that of sound), it is going faster than it's own sound. As a result, a pressure (sound is variation in pressure) wave is produced in the shape of the cone whose vertex is at the nose of the plane, and whose base is behind the plane. The angle opening of the cone depends on the actual speed the plane is traveling at. All of the sound pressure is contained in this cone.
So imagine now this plane in a level flight. Before the plane passes you, you can only see it but you can not hear anything. The pressure cone is trailing behind the plane. Once your ears intersect the edge of this cone, your will hear a very loud sound - the sonic boom. Therefore you will hear the sonic boom once your ears intersect this cone, and not when the plane breaks the sound barrier (as it is commonly misunderstood)
A sonic boom is a specific kind of sound. As an item accelerates through the air it creates a wave of compressed air ahead of it. When that item exceeds the speed of sound, that wave is ruptured, causing a loud burst of sound energy that we have come to know as a sonic boom. You can record and replay that sound, but it would not recreate the conditions that caused the sonic boom in the first place, so it would not ever under any circumstances be another sonic boom.
The sonic boom you hear is caused by something as it passes over the speed of sound. I do not know what actually causes it, but I do know a couple of things about it.
The two most common things that travel over the speed of sound and therefore cause a sonic boom are jets, and bullets.
The reason modern fighter jets have swept back wings is to help eliminate the sonic boom.
Bullets from some firearms go faster than the speed of sound and when they do they have a distinctly different bang than bullets that do not. The faster ones sound more like a crack and the slower ones sound more like a bang.
General Chuck Yeager was the first American to break the sound barrier back in the 40's. He said that travel from approximately 800 feet per second to just over 2,000 feet per second was very turbulent, and as a military man he also related this to bullet travel and determined that firearms that shot bullets at these speeds were not as accurate as others. He was later proven right by testing.
General Yeager also said flying over the 2,000 feet per second mark was very smooth.
You can find a lot of interesting information about this just by putting "speed of sound" or "sonic boom" in your web crawler and go to some of those sites.
Hope this helps.
Basically, a sonic boom is the audible shock wave that an object makes when it travels at the speed or faster than the speed of sound ~761 miles per hour or 1225 kilometers per hour.
Think of sound as a ripple of water. Quiet sounds are small ripples and loud sounds are big waves. When a boat is traveling through a still body of water, the created waves move away from the boat in all directions. If the boat travels fast enough, the waves that are created in front of the boat start to build up on each other because the boat keeps adding more and more waves.
Now take a jet - an object that can actually create sonic booms. When a jet is flying through the air, it is making sound. The sound is also moving through the air (at the speed of sound). When the jet reaches the speed of sound, all the sound waves that the jet is making in front of itself are building up on each other. When this continues, the sound that can be heard is a sonic boom. In reality, the sonic boom is not really a single "boom" but rather a continuous roar of sound. But since we are standing relatively still, we only get hit by a single part of the sound wave.
Sonic boom is commonly used to refer to the shocks caused by the supersonic flight of an aircraft. Sonic booms generate enormous amounts of sound energy, sounding much like an explosion. Thunder is a type of natural sonic boom, created by the rapid heating and expansion of air in a lightning discharge.
A shock wave is a type of propagating disturbance. Like an ordinary wave, it carries energy and can propagate through a medium (solid, liquid or gas) or in some cases in the absence of a material medium, through a field such as the electromagnetic field. Shock waves are characterized by an abrupt, nearly discontinuous change in the characteristics of the medium. Across a shock there is always an extremely rapid rise in pressure, temperature and density of the flow. In supersonic flows, expansion is achieved through an expansion fan. A shock wave travels through most media at a higher speed than an ordinary wave.
Unlike solitons (another kind of nonlinear wave), the energy of a shock wave dissipates relatively quickly with distance. Also, the accompanying expansion wave approaches and eventually merges with the shock wave, partially cancelling it out. Thus the sonic boom associated with the passage of a supersonic aircraft is the sound wave resulting from the degradation and merging of the shock wave and the expansion wave produced by the aircraft.
When a shock wave passes through matter, the total energy is preserved but the energy which can be extracted as work decreases and entropy increases. This for example creates additional drag force on aircraft with shocks.
Why does breaking the sound barrier result in a sonic boom?
Sonic boom is an impulsive noise similar to thunder. It is caused by an object moving faster than sound, about 750 miles per hour at sea level. An aircraft traveling through the atmosphere continuously produces air-pressure waves similar to the water waves caused by a ship's bow. When the aircraft exceeds the speed of sound, these pressure waves combine and form shock waves which travel forward from the generation or "release" point.
As an aircraft flies at supersonic speeds it is continually generating shock waves, dropping sonic boom along its flight path, similar to someone dropping objects from a moving vehicle. From the perspective of the aircraft, the boom appears to be swept backwards as it travels awayfrom the aircraft. If the plane makes a sharp turn or pulls up, the boom will hit the ground in front of the aircraft.
The sound heard on the ground as a "sonic boom" is the sudden onset and release of pressure after the buildup by the shock wave or "peak overpressure." The change in pressure caused by sonic boom is only a few pounds per square foot, about the same pressure change we experience on an elevator as it descends two or three floors, in a much shorter time period. It is the magnitude of this peak overpressure that describes a sonic boom.
What causes the sonic booms produces by supersonic aircraft?
Sonic boom is an impulsive noise similar to thunder. It is caused by an object moving faster than sound -- about 750 miles per hour at sea level. An aircraft traveling through the atmosphere continuously produces air-pressure waves similar to the water waves caused by a ship's bow. When the aircraft exceeds the speed of sound, these pressure waves combine and form shock waves which travel forward from the generation or "release" point.
As an aircraft flies at supersonic speeds it is continually generating shock waves, dropping sonic boom along its flight path, similar to someone dropping objects from a moving vehicle. From the perspective of the aircraft, the boom appears to be swept backwards as it travels away from the aircraft. If the plane makes a sharp turn or pulls up, the boom will hit the ground in front of the aircraft.
The sound heard on the ground as a "sonic boom" is the sudden onset and release of pressure after the buildup by the shock wave or "peak overpressure." The change in pressure caused by sonic boom is only a few pounds per square foot -- about the same pressure change we experience on an elevator as it descends two or three floors -- in a much shorter time period. It is the magnitude of this peak overpressure that describes a sonic boom.
There are two types of booms: N-waves and U-waves. The N-wave is generated from steady flight conditions, and its pressure wave is shaped like the letter "N." N-waves have a front shock to a positive peak overpressure which is followed by a linear decrease in the pressure until the rear shock returns to ambient pressure. The U-wave, or focused boom, is generated from maneuvering flights, and its pressure wave is shaped like the letter "U." U-waves have positive shocks at the front and rear of the boom in which the peak overpressures are increased compared to the N-wave.
For today's supersonic aircraft in normal operating conditions, the peak overpressure varies from less than one pound to about 10 pounds per square foot for a N-wave boom. Peak overpressures for U-waves are amplified two to five times the N-wave, but this amplified overpressure impacts only a very small area when compared to the area exposed to the rest of the sonic boom.
The strongest sonic boom ever recorded was 144 pounds per square foot and it did not cause injury to the researchers who were exposed to it. The boom was produced by a F-4 flying just above the speed of sound at an altitude of 100 feet.
In recent tests, the maximum boom measured during more realistic flight conditions was 21 pounds per square foot. There is a probability that some damage -- shattered glass, for example, will result from a sonic boom. Buildings in good repair should suffer no damage by pressures of less than 16 pounds per square foot. And, typically, community exposure to sonic boom is below two pounds per square foot. Ground motion resulting from sonic boom is rare and is well below structural damage thresholds accepted by the U.S. Bureau of Mines and other agencies.
The sonic boom that you hear is caused by a large pressure change associate with supersonic flight.
When an airplane breaks the sound barrier, a shock wave forms around the plane. The shock wave has a large pressure difference across it with the pressure being higher close to the body of the plane and lower in front of the plane.
As the shock wave gets further away from the plane it usually interacts with something called an expansion fan which weakens the shock wave until it forms something called a Mach wave. Mach waves are essentially just sound waves and they travel at the speed of sound. The Mach wave travels all the way to the ground where we perceive this pressure jump as a loud sound.
When you see a supersonic jet fly overhead, you don't actually hear the sonic boom until after the plane has passed. This is because the sonic boom travels at the speed of sound which is slower than the aircraft.
Just to clarify a point that another answerer brought up, the sonic boom does not occur just at the instant the plane crosses the sound barrier. When the plane crosses the sound barrier, the sonic boom begins, but it doesn't stop. It gets louder and louder as the plane goes above the sound barrier. It is a common misconception that something magical happens when you transition from subsonic to supersonic but in reality it's not that magical.
A sonic boom is the sound associated with the shock waves created by an object traveling through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding much like an explosion. The crack of a supersonic bullet passing overhead is an example of a sonic boom in miniature.
The sound of a sonic boom depends largely on the distance between the observer and the aircraft shape producing the sonic boom. A sonic boom is usually heard as a deep double "boom" as the aircraft is usually some distance away. However, as those who have witnessed landings of space shuttles have heard, when the aircraft is nearby the sonic boom is a sharper "bang" or "crack". The sound is much like the "aerial bombs" used at firework displays. It is a common misconception that only "one" boom is generated during the subsonic to supersonic transition, rather, the boom is continuous along the boom carpet for the entire supersonic flight. As a former Concorde pilot puts it, "You don't actually hear anything on board. All we see is the pressure wave moving down the aeroplane - it gives an indication on the instruments. And that's what we see around Mach 1. But we don't hear the sonic boom or anything like that. That's rather like the wake of ship - it's behind us.".