I know that when light is sent out of a moving object, its speed still remains the same as if it was sent out of a stationary object. Keep in mind that there is red-shift and blue-shift in light waves though. Now, my question is: Do other waves follow the same principle as light waves? If I hit a metal pole with a hammer, would the sound waves traveling through it move faster if the pole was on a moving object versus the pole just sitting still in a stationary position? Or would the speed of sound remain the same, and instead the doppler effect would occur. Also note to yourself that the speed of light changes through mediums (it slows), and the speed of sound can change through mediums as well.
I can't test my question since I'm only 17, but It would be nice for someone to tell me so I can get it off of my mind.
I also wonder, if special relativity doesn't apply to other waves, then how do we know it does to light? Would we notice a change in 30 mph added to lights speed already?|||okkkaayy. Here's a reply.. so stop complaining about not getting replies... hahahaha. I'm sorry, I couldn't resist %26lt;3|||Sound waves or "pressure waves" do get blue or red shifted like light waves (doppler shift), but the actual velocity of the wave won't change. What will change is the wavelength.
Here is a good treatment on the doppler effect.
http://en.wikipedia.org/wiki/Doppler_effect
Tuesday, December 6, 2011
According to the special theory of relativity, physical laws are the same in frames of reference which?
According to the special theory of relativity, physical laws are the same in frames of reference which ...
accelerate.
move at uniform velocity.
move in ellipses.
move in circles.|||move at uniform velocity|||Move at uniform velocity. Any differences in relative speed will cause some time dilation. In special relativity, the time dilation effect is reciprocal. That's a fancy way of saying that as observed from the point of view of any two clocks which are in motion with respect to each other it will always look to you (or your frame of reference) like the other guy's clock is running slower or faster.
accelerate.
move at uniform velocity.
move in ellipses.
move in circles.|||move at uniform velocity|||Move at uniform velocity. Any differences in relative speed will cause some time dilation. In special relativity, the time dilation effect is reciprocal. That's a fancy way of saying that as observed from the point of view of any two clocks which are in motion with respect to each other it will always look to you (or your frame of reference) like the other guy's clock is running slower or faster.
Do all waves apply to special relativity?
I know that when light is sent out of a moving object, its speed still remains the same as if it was sent out of a stationary object. Keep in mind that there is red-shift and blue-shift in light waves though. Now, my question is: Do other waves follow the same principle as light waves? If I hit a metal pole with a hammer, would the sound waves traveling through it move faster if the pole was on a moving object versus the pole just sitting still in a stationary position? Or would the speed of sound remain the same, and instead the doppler effect would occur. Also note to yourself that the speed of light changes through mediums (it slows), and the speed of sound can change through mediums as well.
I can't test my question since I'm only 17, but It would be nice for someone to tell me so I can get it off of my mind.
I also wonder, if special relativity doesn't apply to other waves, then how do we know it does to light? Would we notice a change in 30 mph added to lights speed already?|||When something moves at constant speed ist usually a wave.This is inertial motion as opposed to gravitational motion, where the speed changes with changing distance and time.
Special Relativity does not apply to gravitational motion at all.
So the Only thing it could apply to is wave motion since it moves at constant velocity..The reason is that a wavelenght can be shorten and time of period dilated. The speed of the wave is medium dependent .And a wave is a disturbance in the medium. If light moves as foloowing the rules of a wave and it moves at constant velocity than special relativity would applly to the motion of light.
A wave by definition cannot exist without a medium . If a medium does not exist then the wave doesnot exist.
So if it is believed that a wave propagation can take place without a medium it would go against the definiton of what constitutes a wave.
The responce to the disturbance in the medium is based on the density of the medium. If Space is a medium for a wave and the density is not homogenous,then the speed of the wave is not the same thruout the medium.
In real life motion takes place in a gravity field no matter what the density of the field. So all motion are basically gravitational.However if the density of the gravity field is weak ,that we can aproximate the motion as being inertial.|||special relativity applies to all inertial frames. The first postulate is the main fundamental. the second postulate is in fact derived from the first postulate itself. the first postulate says that you can not conduct any experiment which can tell u whether u r moving with constant velocity, or are at rest.
hence relativity applies to all things in the universe, not only light. However the rest of the things move very slowly, compared to c, hence the effects of relativity are not noticeable. If a sound wave is moving with a speed of, say 20m/s, an obvserver moving with 10m/s in the opp direction will see it move with 30m/s. Actually, the speed observed is slightly less than 30, but the difference just cant be measured.|||SR is based on the observation that in vacuum the speed of light is the same regarless of the movement of the observer. SR applies to inertial frames (ie ones that are not acclerating) but by extension the principle of the constancy of the speed of light must apply to non-inertial frames (can you see why this is obvious? - imagine creating momentarily comoving frames to describe a non-inertial frame instantaneously).
In fact, this speed constancy applies not only to light but to all zero rest mass particles. In particular it applies to all gauge bosons - these are the particles that mediate all of the forces of nature.
Sound does not fall into this category. Sound is a propagating distortion of a medium, and the distortion is actually mediated by the electrostatic force between atoms, and that is mediated of course by photons and they do indeed move at the speed of light. But the distortion (sounds) does not - it moves at a speed determined by the response time of the atoms.
I can't test my question since I'm only 17, but It would be nice for someone to tell me so I can get it off of my mind.
I also wonder, if special relativity doesn't apply to other waves, then how do we know it does to light? Would we notice a change in 30 mph added to lights speed already?|||When something moves at constant speed ist usually a wave.This is inertial motion as opposed to gravitational motion, where the speed changes with changing distance and time.
Special Relativity does not apply to gravitational motion at all.
So the Only thing it could apply to is wave motion since it moves at constant velocity..The reason is that a wavelenght can be shorten and time of period dilated. The speed of the wave is medium dependent .And a wave is a disturbance in the medium. If light moves as foloowing the rules of a wave and it moves at constant velocity than special relativity would applly to the motion of light.
A wave by definition cannot exist without a medium . If a medium does not exist then the wave doesnot exist.
So if it is believed that a wave propagation can take place without a medium it would go against the definiton of what constitutes a wave.
The responce to the disturbance in the medium is based on the density of the medium. If Space is a medium for a wave and the density is not homogenous,then the speed of the wave is not the same thruout the medium.
In real life motion takes place in a gravity field no matter what the density of the field. So all motion are basically gravitational.However if the density of the gravity field is weak ,that we can aproximate the motion as being inertial.|||special relativity applies to all inertial frames. The first postulate is the main fundamental. the second postulate is in fact derived from the first postulate itself. the first postulate says that you can not conduct any experiment which can tell u whether u r moving with constant velocity, or are at rest.
hence relativity applies to all things in the universe, not only light. However the rest of the things move very slowly, compared to c, hence the effects of relativity are not noticeable. If a sound wave is moving with a speed of, say 20m/s, an obvserver moving with 10m/s in the opp direction will see it move with 30m/s. Actually, the speed observed is slightly less than 30, but the difference just cant be measured.|||SR is based on the observation that in vacuum the speed of light is the same regarless of the movement of the observer. SR applies to inertial frames (ie ones that are not acclerating) but by extension the principle of the constancy of the speed of light must apply to non-inertial frames (can you see why this is obvious? - imagine creating momentarily comoving frames to describe a non-inertial frame instantaneously).
In fact, this speed constancy applies not only to light but to all zero rest mass particles. In particular it applies to all gauge bosons - these are the particles that mediate all of the forces of nature.
Sound does not fall into this category. Sound is a propagating distortion of a medium, and the distortion is actually mediated by the electrostatic force between atoms, and that is mediated of course by photons and they do indeed move at the speed of light. But the distortion (sounds) does not - it moves at a speed determined by the response time of the atoms.
Help with a hard special relativity question?
I understand the basic concepts of special relativity, but I can't figure out how to solve this question, remembering that both length and time change.
The star Alpha Centauri is 4 light years away. At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 3 years, as measured by the travellers on the spacecraft?
Thanks.|||It takes the ship 3 years to reach the star while
moving at v. Hence the contracted distance is:
D = v*t = v*3 = 4c*sqrt(1-v^2/c^2)
=%26gt;v = sqrt(16/25)c|||Thank you.
|||1 Lightyear = 9.461 * 10^15 meters
Velocity = Distance/Time
Velocity = 4(9.461 * 10^15m) / (3(60s)(60)(24)(365)) (This value here is the equivalent of 3 years in seconds (3, 60 seconds, 60 minutes, 24 hours, 365 days))
Velocity = 400008455.9m/s
The star Alpha Centauri is 4 light years away. At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 3 years, as measured by the travellers on the spacecraft?
Thanks.|||It takes the ship 3 years to reach the star while
moving at v. Hence the contracted distance is:
D = v*t = v*3 = 4c*sqrt(1-v^2/c^2)
=%26gt;v = sqrt(16/25)c|||Thank you.
Report Abuse
|||1 Lightyear = 9.461 * 10^15 meters
Velocity = Distance/Time
Velocity = 4(9.461 * 10^15m) / (3(60s)(60)(24)(365)) (This value here is the equivalent of 3 years in seconds (3, 60 seconds, 60 minutes, 24 hours, 365 days))
Velocity = 400008455.9m/s
Einstein's Theory of Relativity led to the discovery of what type of energy?
Einstein's Theory of Relativity led to the discovery of what type of energy?|||because of the theory atomic energy was discovered.|||well sweetie I think it didn't lead to the discovery of any energy. unless you mean gravity.... well einstein discovered how gravity works so that doesn't really mean that he discovered the actual thing. just how it works. I hope this helps . good question . -B-|||LMFAO MAN. Doing your homework i see!
Kinetic Energy??? (NO CLUE)|||nuclear|||E=mc^2, nuclear energy. The mass lost when fission occurs can be multiplied by the square of the speed of light. The key word being "lost" What that means is the mass of an atom is more than the combined mass of all of the fission fragments that remain after fission. The difference in mass is what you use as your m. The mass that is lost is called the Binding energy or Mass defect. Protons repel each other normally in classical physics, but when they get incredibly close together a non classical force, called nuclear force causes them to be attracted to each other. This magically makes two protons in a nucleus weigh slightly more than the two protons were they seperate. Also neutrons are in the nucleus and weigh slightly more combined, than alone. A good analogy in nature is phase changes in water, etc. It is called the latent heat of vaporazation, fusion, etc. where potential energy must be added to make water change phase. So at atmospheric pressure, if you add energy at a constant rate, temperature will rise up to 212 F, and will then hold constant at 212 F while all the water flashes to steam gradually, and will not heat above 212 until all the water has flashed to steam. This is energy required to cause a phase change. Mass isn't changed, but density is. In nuclear fission, it is mass that drops to give off energy, but in fusion, energy is added to force nucleus's together to create more mass.|||rest energy, e=mc[squared] means that an object can have energy as long as it has mass
he helped develop the atomic bomb, relativity assisted by recognizing that the nucleus has stored energy in a rest state and can be released via a nucear reaction (fusion or fission)|||more than likely dark energy, since the general theory was to do with space and gravity.....|||Atomic energy. That the Energy (in Joules) contained in an object is equal to its Mass (in grams) times the speed of light (in centimeters per second) squared. That energy and mass are interchangeable by that formula. This was a result of his theory, although the theory is really about the invariance of the speed of light.|||The theory of relativity, or simply relativity, refers specifically to two theories: Albert Einstein's special relativity and general relativity.
The term "relativity" was coined by Max Planck in 1908 to emphasize how special relativity (and later, general relativity) uses the principle of relativity.
The special theory of relativity was proposed in 1905 by Albert Einstein in his article "On the Electrodynamics of Moving Bodies". Some three centuries earlier, Galileo's principle of relativity had stated that all uniform motion was relative, and that there was no absolute and well-defined state of rest; a person on the deck of a ship may be at rest in his opinion, but someone observing from the shore would say that he was moving. Einstein's theory generalized Galilean relativity from only mechanics to all laws of physics including electrodynamics. To stress this point, Einstein not only widened the postulate of relativity, but added the second postulate - that all observers will always measure the speed of light to be the same no matter what their state of uniform linear motion is.[1]
This theory has a variety of surprising consequences that seem to violate common sense, but all have been experimentally verified. Special relativity overthrows Newtonian notions of absolute space and time by stating that distance and time depend on the observer, and that time and space are perceived differently, depending on the observer. It yields the equivalence of matter and energy, as expressed in the mass-energy equivalence formula E = mc², where c is the speed of light in a vacuum. Special relativity agrees with Newtonian mechanics in their common realm of applicability, in experiments in which all velocities are small compared to the speed of light.
The theory was called "special" because it applies the principle of relativity only to inertial frames. Einstein developed general relativity to apply the principle generally, that is, to any frame, and that theory includes the effects of gravity. Special relativity does not account for gravity, but it can deal with accelerations.
Although special relativity makes some quantities relative, such as time, that we would have imagined to be absolute based on everyday experience, it also makes absolute some others that we would have thought were relative. In particular, it states that the speed of light is the same for all observers, even if they are in motion relative to one another. Special relativity reveals that c is not just the velocity of a certain phenomenon - light - but rather a fundamental feature of the way space and time are tied together. In particular, special relativity states that it is impossible for any material object to accelerate to light speed.
Special relativity
Main article: Special relativity
Special relativity is a theory of the structure of spacetime. It was introduced in Albert Einstein's 1905 paper "On the Electrodynamics of Moving Bodies". Special relativity is based on two postulates which are contradictory in classical mechanics:
The laws of physics are the same for all observers in uniform motion relative to one another (Galileo's principle of relativity),
The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the source of the light.
The resultant theory has many surprising consequences. Some of these are:
Time dilation: Moving clocks tick slower than an observer's "stationary" clock.
Length contraction: Objects are observed to be shortened in the direction that they are moving with respect to the observer.
Relativity of simultaneity: two events that appear simultaneous to an observer A will not be simultaneous to an observer B if B is moving with respect to A.
Mass-energy equivalence: E = mc², energy and mass are equivalent and transmutable.
The defining feature of special relativity is the replacement of the Galilean transformations of classical mechanics by the Lorentz transformations. (See Maxwell's equations of electromagnetism and introduction to special relativity).
General relativity
Main article: General relativity
General relativity is a theory of gravitation developed by Einstein in the years 1907–1915. The development of general relativity began with the equivalence principle, under which the states of accelerated motion and being at rest in a gravitational field (for example when standing on the surface of the Earth) are physically identical. The upshot of this is that free fall is inertial motion: In other words an object in free fall is falling because that is how objects move when there is no force being exerted on them, instead of this being due to the force of gravity as is the case in classical mechanics. This is incompatible with classical mechanics and special relativity because in those theories inertially moving objects cannot accelerate with respect to each other, but objects in free fall do so. To resolve this difficulty Einstein first proposed that spacetime is curved. In 1915, he devised the Einstein field equations which relate the curvature of spacetime with the mass, energy, and momentum within it.
Some of the consequences of general relativity are:
Time goes slower at lower gravitational potentials. This is called gravitational time dilation.
Orbits precess in a way unexpected in Newton's theory of gravity. (This has been observed in the orbit of Mercury and in binary pulsars).
Even rays of light (which are weightless) bend in the presence of a gravitational field.
The Universe is expanding, and the far parts of it are moving away from us faster than the speed of light. This does not contradict the theory of special relativity, since it is space itself that is expanding.
Frame-dragging, in which a rotating mass "drags along" the space time around it.
Technically, general relativity is a metric theory of gravitation whose defining feature is its use of the Einstein field equations. The solutions of the field equations are metric tensors which define the topology of the spacetime and how objects move intertially.|||the splitting of the atom|||??? it didn't lead to the discovery of any energy. unless you mean gravity.... well einstein discovered how gravity works so that doesn't really mean that he discovered the actual thing. just how it works...
Kinetic Energy??? (NO CLUE)|||nuclear|||E=mc^2, nuclear energy. The mass lost when fission occurs can be multiplied by the square of the speed of light. The key word being "lost" What that means is the mass of an atom is more than the combined mass of all of the fission fragments that remain after fission. The difference in mass is what you use as your m. The mass that is lost is called the Binding energy or Mass defect. Protons repel each other normally in classical physics, but when they get incredibly close together a non classical force, called nuclear force causes them to be attracted to each other. This magically makes two protons in a nucleus weigh slightly more than the two protons were they seperate. Also neutrons are in the nucleus and weigh slightly more combined, than alone. A good analogy in nature is phase changes in water, etc. It is called the latent heat of vaporazation, fusion, etc. where potential energy must be added to make water change phase. So at atmospheric pressure, if you add energy at a constant rate, temperature will rise up to 212 F, and will then hold constant at 212 F while all the water flashes to steam gradually, and will not heat above 212 until all the water has flashed to steam. This is energy required to cause a phase change. Mass isn't changed, but density is. In nuclear fission, it is mass that drops to give off energy, but in fusion, energy is added to force nucleus's together to create more mass.|||rest energy, e=mc[squared] means that an object can have energy as long as it has mass
he helped develop the atomic bomb, relativity assisted by recognizing that the nucleus has stored energy in a rest state and can be released via a nucear reaction (fusion or fission)|||more than likely dark energy, since the general theory was to do with space and gravity.....|||Atomic energy. That the Energy (in Joules) contained in an object is equal to its Mass (in grams) times the speed of light (in centimeters per second) squared. That energy and mass are interchangeable by that formula. This was a result of his theory, although the theory is really about the invariance of the speed of light.|||The theory of relativity, or simply relativity, refers specifically to two theories: Albert Einstein's special relativity and general relativity.
The term "relativity" was coined by Max Planck in 1908 to emphasize how special relativity (and later, general relativity) uses the principle of relativity.
The special theory of relativity was proposed in 1905 by Albert Einstein in his article "On the Electrodynamics of Moving Bodies". Some three centuries earlier, Galileo's principle of relativity had stated that all uniform motion was relative, and that there was no absolute and well-defined state of rest; a person on the deck of a ship may be at rest in his opinion, but someone observing from the shore would say that he was moving. Einstein's theory generalized Galilean relativity from only mechanics to all laws of physics including electrodynamics. To stress this point, Einstein not only widened the postulate of relativity, but added the second postulate - that all observers will always measure the speed of light to be the same no matter what their state of uniform linear motion is.[1]
This theory has a variety of surprising consequences that seem to violate common sense, but all have been experimentally verified. Special relativity overthrows Newtonian notions of absolute space and time by stating that distance and time depend on the observer, and that time and space are perceived differently, depending on the observer. It yields the equivalence of matter and energy, as expressed in the mass-energy equivalence formula E = mc², where c is the speed of light in a vacuum. Special relativity agrees with Newtonian mechanics in their common realm of applicability, in experiments in which all velocities are small compared to the speed of light.
The theory was called "special" because it applies the principle of relativity only to inertial frames. Einstein developed general relativity to apply the principle generally, that is, to any frame, and that theory includes the effects of gravity. Special relativity does not account for gravity, but it can deal with accelerations.
Although special relativity makes some quantities relative, such as time, that we would have imagined to be absolute based on everyday experience, it also makes absolute some others that we would have thought were relative. In particular, it states that the speed of light is the same for all observers, even if they are in motion relative to one another. Special relativity reveals that c is not just the velocity of a certain phenomenon - light - but rather a fundamental feature of the way space and time are tied together. In particular, special relativity states that it is impossible for any material object to accelerate to light speed.
Special relativity
Main article: Special relativity
Special relativity is a theory of the structure of spacetime. It was introduced in Albert Einstein's 1905 paper "On the Electrodynamics of Moving Bodies". Special relativity is based on two postulates which are contradictory in classical mechanics:
The laws of physics are the same for all observers in uniform motion relative to one another (Galileo's principle of relativity),
The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the source of the light.
The resultant theory has many surprising consequences. Some of these are:
Time dilation: Moving clocks tick slower than an observer's "stationary" clock.
Length contraction: Objects are observed to be shortened in the direction that they are moving with respect to the observer.
Relativity of simultaneity: two events that appear simultaneous to an observer A will not be simultaneous to an observer B if B is moving with respect to A.
Mass-energy equivalence: E = mc², energy and mass are equivalent and transmutable.
The defining feature of special relativity is the replacement of the Galilean transformations of classical mechanics by the Lorentz transformations. (See Maxwell's equations of electromagnetism and introduction to special relativity).
General relativity
Main article: General relativity
General relativity is a theory of gravitation developed by Einstein in the years 1907–1915. The development of general relativity began with the equivalence principle, under which the states of accelerated motion and being at rest in a gravitational field (for example when standing on the surface of the Earth) are physically identical. The upshot of this is that free fall is inertial motion: In other words an object in free fall is falling because that is how objects move when there is no force being exerted on them, instead of this being due to the force of gravity as is the case in classical mechanics. This is incompatible with classical mechanics and special relativity because in those theories inertially moving objects cannot accelerate with respect to each other, but objects in free fall do so. To resolve this difficulty Einstein first proposed that spacetime is curved. In 1915, he devised the Einstein field equations which relate the curvature of spacetime with the mass, energy, and momentum within it.
Some of the consequences of general relativity are:
Time goes slower at lower gravitational potentials. This is called gravitational time dilation.
Orbits precess in a way unexpected in Newton's theory of gravity. (This has been observed in the orbit of Mercury and in binary pulsars).
Even rays of light (which are weightless) bend in the presence of a gravitational field.
The Universe is expanding, and the far parts of it are moving away from us faster than the speed of light. This does not contradict the theory of special relativity, since it is space itself that is expanding.
Frame-dragging, in which a rotating mass "drags along" the space time around it.
Technically, general relativity is a metric theory of gravitation whose defining feature is its use of the Einstein field equations. The solutions of the field equations are metric tensors which define the topology of the spacetime and how objects move intertially.|||the splitting of the atom|||??? it didn't lead to the discovery of any energy. unless you mean gravity.... well einstein discovered how gravity works so that doesn't really mean that he discovered the actual thing. just how it works...
Whats the problem between the theory of Relativity and Quantum Physics?
I understand that the Theory of Relativity explains the space/time fabric of the universe, gravity effect on it, energy and mass/the speed of light, and ect. and that Quantum physics is about atomic sized partials (i know less about it than Relativity) but i have herd that the two theory's don't quite agree with each other i heard some explanations but i don't quite understand them.|||General relativity is a classical theory--it explains the behavior of objects at low energy scales.
Quantum mechanics describes the behavior of objects at very high energy and small distance scales.
Because the quantum of gravity carries so little energy, the quantum nature of gravity has never manifest itself in any experiment or natural phenomenon. General relativity works fine. But given enough energy (maybe more than we will ever generate experimentally), GR should break down.
There are theories of quantum gravity that have GR as a low energy limit, just as classical gravity is a low mass, long distance limit of GR. The problem with them, though, is that they are non-renormalizable. There are infinite energies that can't be ignored or hand-waved away as they are in other quantum field theories (because gravity couples to energy). String theory does successfully reconcile classical GR with quantum mechanics, but we are a long way from being able to test it in any other way.
Quantum mechanics describes the behavior of objects at very high energy and small distance scales.
Because the quantum of gravity carries so little energy, the quantum nature of gravity has never manifest itself in any experiment or natural phenomenon. General relativity works fine. But given enough energy (maybe more than we will ever generate experimentally), GR should break down.
There are theories of quantum gravity that have GR as a low energy limit, just as classical gravity is a low mass, long distance limit of GR. The problem with them, though, is that they are non-renormalizable. There are infinite energies that can't be ignored or hand-waved away as they are in other quantum field theories (because gravity couples to energy). String theory does successfully reconcile classical GR with quantum mechanics, but we are a long way from being able to test it in any other way.
How clear do I need to be on Newtonian mechanics in order to understand general relativity?
for example, if I dont understand 3-4 problems per chapter in a book of fundamentals, will it severely hinder me from understanding relativity|||General relativity is non-intuitive and really hard to fully understand. It is really easy to say that the speed of light is constant and that time slows as velocity increases and mass increases as velocity increases, but it doesn't really make a whole lot of sense. So, if you are having trouble with Newtonian mechanics, which does make a lot of sense, then I think you are going to have trouble with relativity.
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