Physics Book - User contributions [en]

Sound Barrier

2015-11-30T06:18:15Z

Pnguyen70: /* External links */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===
Named after Ernst Mach, Mach is a measurement of the ratio of flow velocity past a boundary to the speed of sound (in the local area, as speed of sound depends on the medium).

[[File:machformula.JPG]]
where mu represents the flow velocity and c represents the local speed of sound in the medium. This means that mach is not one set number as the speed of sound is directly correlated to the temperature of the medium. The higher the temperature, the higher the speed of sound in that medium. The formula above is the simplistic form as when the flows become compressible or when the object is at a subsonic speed is much more complicated. For the sake of the topic, the mentioned formula is the only one we will talk about.

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T06:18:03Z

Pnguyen70: /* Further reading */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===
Named after Ernst Mach, Mach is a measurement of the ratio of flow velocity past a boundary to the speed of sound (in the local area, as speed of sound depends on the medium).

[[File:machformula.JPG]]
where mu represents the flow velocity and c represents the local speed of sound in the medium. This means that mach is not one set number as the speed of sound is directly correlated to the temperature of the medium. The higher the temperature, the higher the speed of sound in that medium. The formula above is the simplistic form as when the flows become compressible or when the object is at a subsonic speed is much more complicated. For the sake of the topic, the mentioned formula is the only one we will talk about.

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T06:17:23Z

Pnguyen70: /* Mach */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===
Named after Ernst Mach, Mach is a measurement of the ratio of flow velocity past a boundary to the speed of sound (in the local area, as speed of sound depends on the medium).

[[File:machformula.JPG]]
where mu represents the flow velocity and c represents the local speed of sound in the medium. This means that mach is not one set number as the speed of sound is directly correlated to the temperature of the medium. The higher the temperature, the higher the speed of sound in that medium. The formula above is the simplistic form as when the flows become compressible or when the object is at a subsonic speed is much more complicated. For the sake of the topic, the mentioned formula is the only one we will talk about.

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T06:09:31Z

Pnguyen70: /* Mach */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===
Is a measurement of the ratio of flow velocity past a boundary to the speed of sound (in the local area, as speed of sound depends on the medium).
[[File:machformula.JPG]]

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

File:Machformula.JPG

2015-11-30T06:09:10Z

Pnguyen70:

Sound Barrier

2015-11-30T06:01:34Z

Pnguyen70: /* Mach */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===
Is a measurement

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T05:58:44Z

Pnguyen70: /* Shock Waves */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Sonic Boom==
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T05:57:56Z

Pnguyen70: /* Sound Barrier */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]]
Speed of object = Speed of sound
[[File:speedgreatersound.JPG]]
Speed of object > Speed of sound

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Shock Waves==
These are regions of increased air pressure and temperature that are produced by any object moving through air and the most common example of a shock wave is the sonic boom.

===Sonic Boom===
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Sound Barrier

2015-11-30T05:57:06Z

Pnguyen70: /* Sound Barrier */

==Sound Barrier==
Sound Barrier is a common term referring to the unusual amounts of drag in a fluid when an object approaches the speed of sound, which is about 1125 ft/s or 767 mph in dry air. First observed during World War II, the sound barrier doesn't exist as a physical limitation but rather represents the difficulty at which objects near the speed of sound experience when trying to accelerate further. The point at which the object does exceed this threshold, a shock wave is produced. The faster the object, the more conical the shock wave. When the speed of an object equals the speed of sound (v = c) then a pile up occurs and creates the "barrier" that was initially thought to be impassable. However, when an object surpasses the speed of sound (v > c, where c is the speed of sound) the shock waves become more conical in form as they lag behind the object. The edge of the cone is a supersonic wave front, known as a shock wave. The following phenomenon is depicted below.

[[File:Speedequalsound.JPG]] [[File:speedgreatersound.JPG]]

A common more easily understood example is that of a boat moving through water. The slow boat creates waves both behind and in front of it as the waves propagate faster than the boat can move. However once the boat starts moving faster than the waves can propagate, a wake is formed. Akin to the boat metaphor, an airplane moving through air creates sound waves and the resultant "wake" that is formed when moving supersonic speeds is called a sonic boom.

[[File:shockwaves.gif]]

==Shock Waves==
These are regions of increased air pressure and temperature that are produced by any object moving through air and the most common example of a shock wave is the sonic boom.

===Sonic Boom===
The sonic boom is heard once the object passes the speed of sound. It is the result of all the compressible regions or high pressure regions in a wave front reaching the observer all at the same time instead of the usual delayed observed in the Doppler effect.
[[File:sonicboom.gif]] [[File:navyairplane.jpg]]

===Overcoming Sound Barrier Limitations===
====Area Rule====
The Whitecomb Area rule (A.K.A transonic area rule) is an innovation in design to reduce the drag of an object at supersonic speeds created by Richard Whitecomb. It was created in attempts to limit the effects of the powerful and sudden drag objects experience when approaching the speed of sound. Relating both the longitudinal and latitude cross section of an object, usually an aircraft, the rule states.
1. Two airplanes with the same longitudinal cross sectional area have the same wave drag completely independent of how area is distributed laterally.
2. To avoid formation of strong shock waves (and thus a decrease in power) the total area distribution must be smooth.
[[File:arearule.jpg]]

As important as this rule is, it has recently been rendered relatively obsolete with the advent of newer and more powerful engines in airplanes which give the vehicle enough power to render the drag a small factor.

===Mach===

==Connectedness==
#The Sound Barrier is a common problem that many commercial vehicles are trying to overcome. As a mechanical engineer, it is my hope that I would do work in improving the efficiency of airplanes and vehicles in moving in supersonic speeds.

==History==
Despite the relatively recent claim of breaking the sound barrier, it was broken long ago. The tip of a whip, when properly swung, actually breaks the sound barrier creating a shock wave that we hear as the audible crack. However, in terms of vehicles moving the speed of sound, it took much longer. Initial attempts to break the sound barrier often ended in failure due to the difficulty in controlling aircraft at supersonic speeds. While the barrier was often claimed to be broken when a vehicle entered a dive, most of these cases ended in the pilot crashing or were faulty. It wasn't until October 1947 in which Air Force pilot, Chuck Yeager, broke the sound barrier and reached mach .997, which has been argued to actually be a little above mach 1 but measurements were faulty.

== See also ==
http://www.physicsbook.gatech.edu/Doppler_Effect

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==
#http://science.howstuffworks.com/question73.htm
#http://www.physicscentral.com/explore/action/shockwaves.cfm
#http://www.physicsclassroom.com/class/sound/Lesson-3/The-Doppler-Effect-and-Shock-Waves
#https://en.wikipedia.org/wiki/Swept_wing
#https://en.wikipedia.org/wiki/Area_rule
#http://mathforum.org/library/drmath/view/56298.html
#http://www.airspacemag.com/need-to-know/why-dont-todays-fighters-have-narrow-waists-8647157/?no-ist

[[Category:Which Category did you place this in?]]

Pnguyen70:

File:Navyairplane.jpg

2015-11-30T05:35:13Z

Pnguyen70:

Sound Barrier

Sound Barrier

2015-11-30T04:26:55Z

Pnguyen70: /* Sound Barrier */

==Sound Barrier==

====A Mathematical Model====

[[File:shockwaves.gif]]

===First Law===

==Sonic Boom==

===Mathematical Models===

===Examples===

==Connectedness==
#How is this topic connected to something that you are interested in?
#How is it connected to your major?
#Is there an interesting industrial application?

==History==

== See also ==

Are there related topics or categories in this wiki resource for the curious reader to explore? How does this topic fit into that context?

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==

[[Category:Which Category did you place this in?]]

File:Shockwaves.gif

2015-11-30T04:25:49Z

Pnguyen70:

Sound Barrier

2015-11-29T22:51:52Z

Pnguyen70: /* Sound Barrier */

==Sound Barrier==

====A Mathematical Model====

===First Law===

==Sonic Boom==

===Mathematical Models===

===Examples===

==Connectedness==
#How is this topic connected to something that you are interested in?
#How is it connected to your major?
#Is there an interesting industrial application?

==History==

== See also ==

Are there related topics or categories in this wiki resource for the curious reader to explore? How does this topic fit into that context?

===Further reading===

Books, Articles or other print media on this topic

===External links===

Internet resources on this topic

==References==

[[Category:Which Category did you place this in?]]

2015-11-29T21:43:16Z

Pnguyen70: /* Sound */

__NOTOC__
Welcome to the Georgia Tech Wiki for Intro Physics. This resources was created so that students can contribute and curate content to help those with limited or no access to a textbook. When reading this website, please correct any errors you may come across. If you read something that isn't clear, please consider revising it!

Looking to make a contribution?
#Pick a specific topic from intro physics
#Add that topic, as a link to a new page, under the appropriate category listed below by editing this page.
#Copy and paste the default [[Template]] into your new page and start editing.

Please remember that this is not a textbook and you are not limited to expressing your ideas with only text and equations. Whenever possible embed: pictures, videos, diagrams, simulations, computational models (e.g. Glowscript), and whatever content you think makes learning physics easier for other students.

== Source Material ==
All of the content added to this resource must be in the public domain or similar free resource. If you are unsure about a source, contact the original author for permission. That said, there is a surprisingly large amount of introductory physics content scattered across the web. Here is an incomplete list of intro physics resources (please update as needed).
* A physics resource written by experts for an expert audience [https://en.wikipedia.org/wiki/Portal:Physics Physics Portal]
* A wiki book on modern physics [https://en.wikibooks.org/wiki/Modern_Physics Modern Physics Wiki]
* The MIT open courseware for intro physics [http://ocw.mit.edu/resources/res-8-002-a-wikitextbook-for-introductory-mechanics-fall-2009/index.htm MITOCW Wiki]
* An online concept map of intro physics [http://hyperphysics.phy-astr.gsu.edu/hbase/hph.html HyperPhysics]
* Interactive physics simulations [https://phet.colorado.edu/en/simulations/category/physics PhET]
* OpenStax algebra based intro physics textbook [https://openstaxcollege.org/textbooks/college-physics College Physics]
* The Open Source Physics project is a collection of online physics resources [http://www.opensourcephysics.org/ OSP]
* A resource guide compiled by the [http://www.aapt.org/ AAPT] for educators [http://www.compadre.org/ ComPADRE]

== Organizing Categories ==
These are the broad, overarching categories, that we cover in two semester of introductory physics. You can add subcategories or make a new category as needed. A single topic should direct readers to a page in one of these catagories.

<div class="toccolours mw-collapsible mw-collapsed">
===Interactions===
<div class="mw-collapsible-content">
*[[Kinds of Matter]]
*[[Detecting Interactions]]
*[[Fundamental Interactions]]
*[[System & Surroundings]]
*[[Newton's First Law of Motion]]
*[[Newton's Second Law of Motion]]
*[[Newton's Third Law of Motion]]
*[[Gravitational Force]]
*[[Terminal Velocity and Friction Due to Air]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Theory===
<div class="mw-collapsible-content">
*[[Einstein's Theory of Special Relativity]]
*[[Quantum Theory]]

</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Notable Scientists===
<div class="mw-collapsible-content">
*[[Albert Einstein]]
*[[Ernest Rutherford]]
*[[Joseph Henry]]
*[[Michael Faraday]]
*[[J.J. Thomson]]
*[[James Maxwell]]
*[[Robert Hooke]]
*[[Marie Curie]]
*[[Carl Friedrich Gauss]]
*[[Nikola Tesla]]
*[[Andre Marie Ampere]]
*[[Sir Isaac Newton]]
*[[J. Robert Oppenheimer]]
*[[Oliver Heaviside]]
*[[Rosalind Franklin]]
*[[Erwin Schrödinger]]
*[[Enrico Fermi]]
*[[Robert J. Van de Graaff]]
*[[Charles de Coulomb]]
*[[Hans Christian Ørsted]]
*[[Philo Farnsworth]]
*[[Niels Bohr]]
*[[Georg Ohm]]
*[[Galileo Galilei]]
*[[Gustav Kirchhoff]]
*[[Max Planck]]
*[[Heinrich Hertz]]
*[[Edwin Hall]]
*[[James Watt]]
*[[Josiah Willard Gibbs]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Properties of Matter===
<div class="mw-collapsible-content">
*[[Mass]]
*[[Velocity]]
*[[Density]]
*[[Charge]]
*[[Spin]]
*[[SI Units]]

</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Contact Interactions===
<div class="mw-collapsible-content">
* [[Young's Modulus]]
* [[Friction]]
* [[Tension]]
* [[Hooke's Law]]
*[[Centripetal Force and Curving Motion]]
*[[Compression or Normal Force]]
* [[Length and Stiffness of an Interatomic Bond]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Momentum===
<div class="mw-collapsible-content">
* [[Vectors]]
* [[Kinematics]]
* [[Predicting Change in multiple dimensions]]
* [[Momentum Principle]]
* [[Impulse Momentum]]
* [[Curving Motion]]
* [[Multi-particle Analysis of Momentum]]
* [[Iterative Prediction]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Angular Momentum===
<div class="mw-collapsible-content">
* [[The Moments of Inertia]]
* [[Rotation]]
* [[Torque]]
*[[Systems with Zero Torque]]
*[[Systems with Nonzero Torque]]
* [[Right Hand Rule]]
* [[Angular Velocity]]
* [[Predicting a Change in Rotation]]
* [[Conservation of Angular Momentum]]
*[[Rotational Angular Momentum]]
*[[Total Angular Momentum]]

</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Energy===
<div class="mw-collapsible-content">
*[[The Energy Principle]]
*[[Predicting Change]]
*[[Rest Mass Energy]]
*[[Kinetic Energy]]
*[[Potential Energy]]
*[[Work]]
*[[Thermal Energy]]
*[[Conservation of Energy]]
*[[Electric Potential]]
*[[Energy Transfer due to a Temperature Difference]]
*[[Gravitational Potential Energy]]
*[[Point Particle Systems]]
*[[Real Systems]]
*[[Spring Potential Energy]]
*[[Internal Energy]]
*[[Translational, Rotational and Vibrational Energy]]
*[[Franck-Hertz Experiment]]
*[[Power]]
*[[Energy Graphs]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Collisions===
<div class="mw-collapsible-content">
*[[Collisions]]
*[[Maximally Inelastic Collision]]
*[[Elastic Collisions]]
*[[Inelastic Collisions]]
*[[Head-on Collision of Equal Masses]]
*[[Head-on Collision of Unequal Masses]]
*[[Rutherford Experiment and Atomic Collisions]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Fields===
<div class="mw-collapsible-content">
* [[Electric Field]] of a
** [[Point Charge]]
** [[Electric Dipole]]
** [[Capacitor]]
** [[Charged Rod]]
** [[Charged Ring]]
** [[Charged Disk]]
** [[Charged Spherical Shell]]
** [[Charged Cylinder]]
**[[A Solid Sphere Charged Throughout Its Volume]]
*[[Electric Potential]]
**[[Potential Difference in a Uniform Field]]
**[[Potential Difference of point charge in a non-Uniform Field]]
**[[Sign of Potential Difference]]
*[[Electric Force]]
*[[Polarization]]
*[[Charge Motion in Metals]]
*[[Magnetic Field]]
**[[Right-Hand Rule]]
**[[Direction of Magnetic Field]]
**[[Magnetic Field of a Long Straight Wire]]
**[[Magnetic Field of a Loop]]
**[[Bar Magnet]]
**[[Magnetic Force]]
**[[Hall Effect]]
**[[Lorentz Force]]
**[[Biot-Savart Law]]
**[[Biot-Savart Law for Currents]]
**[[Integration Techniques for Magnetic Field]]
**[[Sparks in Air]]
**[[Motional Emf]]
**[[Detecting a Magnetic Field]]
**[[Moving Point Charge]]
**[[Non-Coulomb Electric Field]]
**[[Motors and Generators]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Simple Circuits===
<div class="mw-collapsible-content">
*[[Components]]
*[[Steady State]]
*[[Non Steady State]]
*[[Node Rule]]
*[[Loop Rule]]
*[[Power in a circuit]]
*[[Ammeters,Voltmeters,Ohmmeters]]
*[[Current]]
*[[Ohm's Law]]
*[[RC]]
*[[Circular Loop of Wire]]
*[[RL Circuit]]
*[[LC Circuit]]
*[[Surface Charge Distributions]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Maxwell's Equations===
<div class="mw-collapsible-content">
*[[Gauss's Flux Theorem]]
**[[Electric Fields]]
**[[Magnetic Fields]]
*[[Ampere's Law]]
*[[Faraday's Law]]
**[[Curly Electric Fields]]
**[[Inductance]]
**[[Lenz's Law]]
***[[Lenz Effect and the Jumping Ring]]
*[[Ampere-Maxwell Law]]
**[[Superconducters]]
</div>
</div>

<div class="toccolours mw-collapsible mw-collapsed">

===Radiation===
<div class="mw-collapsible-content">
*[[Producing a Radiative Electric Field]]
*[[Sinusoidal Electromagnetic Radiaton]]
*[[Lenses]]
*[[Energy and Momentum Analysis in Radiation]]
*[[Electromagnetic Propagation]]
</div>
</div>
<div class="toccolours mw-collapsible mw-collapsed">

===Sound===
<div class="mw-collapsible-content">
*[[Doppler Effect]]
*[[Nature, Behavior, and Properties of Sound]]
*[[Resonance]]
*[[Sound Barrier]]
</div>
</div>
*[[blahb]]
</div>
</div>

== Resources ==
* Commonly used wiki commands [https://en.wikipedia.org/wiki/Help:Cheatsheet Wiki Cheatsheet]
* A guide to representing equations in math mode [https://en.wikipedia.org/wiki/Help:Displaying_a_formula Wiki Math Mode]
* A page to keep track of all the physics [[Constants]]
* An overview of [[VPython]]