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goozooloo
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Could some one tell me what is it called in physics (name of property etc. ) that does not allow air particles to move past the speed of sound?
That isn't really what is happening. The shock wave is a plain, ordinary sound wave that due to the speed of the aircraft, can't outrun the aircraft. Sub-sonic aircraft push pressure waves out in a circular (from the ground) pattern. Pile these circles up and you get a cone, with all the waves concentrated on the "surface" of the cone.goozooloo said:Well basically, when an aircraft moves faster than the speed of sound it tries to push the air along that same speed right? but the reason for the sonic boom is that the air cannot excede that limit. what causes this to occur?
thanks for ur reply
Remember also that all motion is relative, and except in the passing of the wave and friction from the plane, the air molecules don't actually need to be moving much relative to the ground. In fact, if air molecules are being pushed at high speed, that's an indicator of high drag. Still, when the Space Shuttle blasts into the atmosphere at 10,000 mph, air molecules are going to bounce off that blunt nose at 10,000 mph. In fact, that's what keeps it cool: the bluntness pushes air out in front of it like a snow-plow, keeping the shock wave (and it's enormous pressure induced temperature rise) away from the space shuttle).Me said:The best explanation I've seen is using water drops: if you drip water into a pool, concentric circles form as the wave expands from where the drop hit. If you do a steady drip, drip, drip, these waves will continually move away from the impact point. If you start to move the impact point slowly, the waves will still be able to move forward away from the impact point and you'll end up with circles that are not concentric, but still moving away from the impact point in all directions. If you move faster than the waves can move, all the circles you make will be behind the impact point, and their diameters will be larger the further from the impact point, forming a cone. HERE is a picture of the phenomena using a plane, but the circles are there...
goozooloo said:thats why the speed of sound becomes higher and higher as air density gets lower with gains in altitude. Just what i think, if you would please correct me if I am wrong.
Thanks
jaap de vries said:Actually this is wrong. By gaining altitude the speed of sound decreases because of decrease in temperature a = (T*gamma*R)^1/2. I don't see how the soundspeed would go up with decrease in density where did you read that??
Clausius2 said:Actually temperature arises from upper stratosphere layers on.
Yes, the molecules would be moving fast and transfer all that energy (the speed of sound depends on temperature), but then those molecules would need to do a big billiards game to send all that energy through the atmosphere. The atmosphere is big, so the energy quickly gets absorbed into a standard shockwave based on the prevaling temperature.goozooloo said:however you sed that the air molecule bouncing off the nose of the space shuttle is still traveling at 10,000 km/h, if so then why doesn't the shockwave travel at that speed since its carried by those molecules. I think the effect here is friction, that's why the speed of sound becomes higher and higher as air density gets lower with gains in altitude. Just what i think, if you would please correct me if I am wrong.
Thanks
No: temperature is average kinetic energy of the particles, not kinetic energy per unit volume - so the density doesn't matter.Isnt it- its "hot" in the upper atmosphere because the air molecules are moving so fast, however, they are so far and few between, it feels very cold. Yes? No? Maybe so?
The physics property that prevents air particles from moving faster than the speed of sound in a sonic boom is called the "sound barrier." This is a result of the air particles compressing and creating a shock wave at the leading edge of the object traveling at supersonic speeds.
The speed of sound plays a crucial role in the formation of a sonic boom. When an object travels at supersonic speeds, it creates a shock wave due to the compression of air particles. This shock wave is what we hear as a loud noise, which is the sonic boom. The speed at which this shock wave travels is equal to the speed of sound, hence why it is called the "sound barrier."
A sonic boom is the loud noise produced when an object travels at supersonic speeds, while a sonic boom cloud is the visible cloud-like formation that is sometimes seen during a sonic boom. This cloud is formed due to the sudden drop in pressure and temperature behind the shock wave, causing the water vapor in the air to condense and form a cloud.
Yes, sonic booms can be heard on the ground, but only if the object creating the sonic boom is traveling at supersonic speeds at a low altitude. If the object is high enough in the sky, the sound can dissipate before reaching the ground. Additionally, the intensity of the sonic boom decreases as it travels farther from the source, so it may not be as loud as it is closer to the source.
Scientists and engineers have been working on ways to reduce the intensity of sonic booms, as they can be disruptive and potentially damaging to structures and wildlife. One solution is to design aircrafts with sleeker and more aerodynamic shapes, which can help reduce the intensity of the shock wave. Another approach is to use technology such as "super-cavitating" vehicles, which create a bubble of air around them, reducing the pressure and shock waves as they move through the air.