Examples of speed of light in the following topics:
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- But what exactly is the speed of light?
- It is just that: the speed of a photon or light particle.
- where v = actual velocity of light moving through the medium, c = speed of light in a vacuum, and n = refractive index of medium.
- As mentioned earlier, the speed of light (usually of light in a vacuum) is used in many areas of physics.
- Relate speed of light with the index of refraction of the medium
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- The speed of light in vacuum is a universal physical constant crucial to many areas of physics.
- The speed of light in vacuum, commonly denoted c, is a universal physical constant that is crucial to many areas of physics.
- The first quantitative estimate of the speed of light was made in 1676 by Rømer.
- The speed at which light waves propagate in vacuum is independent both of the motion of the wave source and of the inertial frame of reference of the observer.
- Discuss the invariance of the speed of light and identify the value of that speed in vacuum
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- In special relativity, an object that has a mass cannot travel at the speed of light.
- As the object approaches the speed of light, the object's energy and momentum increase without bound .
- Tolman pictured left of Albert Einstein here in 1934 as which holds for all particles, including those moving at the speed of light.
- The relativistic kinetic energy increases to infinity when an object approaches the speed of light, this indicates that no body with mass can reach the speed of light.
- Evaluate possibility for an object to travel at the speed of light
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- Since special relativity dictates that the speed of light is the same in all frames of reference, light shone from the front of a moving car can't go faster than light from a stationary lamp.
- Using a Michelson interferometer, Hyppolite Fizeau measured the speed of light in a fluid moving parallel to the light in 1851 .
- The speed of light in the fluid is slower than the speed of light in vacuum, and it changes if the fluid is moving along with the light.
- The interference pattern can be analyzed to determine the speed of light traveling along each leg of the tube.
- Express velocity-addition formulas for objects at speeds much less and approaching the speed of light
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- It also results in a prediction that the speed of light can vary from one reference frame to another.
- It is important to note that for speeds much less than the speed of light, Newtonian momentum and relativistic momentum are approximately the same.
- Thus, it is necessary to employ the expression for relativistic momentum when one is dealing with speeds near the speed of light .
- This figure illustrates that relativistic momentum approaches infinity as the speed of light is approached.
- Compare Newtonian and relativistic momenta for objects at speeds much less and approaching the speed of light
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- Relativistic kinetic energy can be expressed as: $E_{k} = \frac{mc^{2}}{\sqrt{1 - (v/c)^{2})}} - mc^{2}$ where $m$ is rest mass, $v$ is velocity, $c$ is speed of light.
- If the speed of a body is a significant fraction of of the speed of light, it is necessary to employ special relativity to calculate its kinetic energy.
- Using $m$ for rest mass, $v$ and $\nu$ for the object's velocity and speed respectively, and $c$ for the speed of light in vacuum, the relativistic expression for linear momentum is:
- The equation shows that the energy of an object approaches infinity as the velocity $v$ approaches the speed of light $c$.
- Compare classical and relativistic kinetic energies for objects at speeds much less and approaching the speed of light
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- The speed of light varies in a precise manner with the material it traverses.
- The change in direction of the light ray depends on how the speed of light changes.
- The change in the speed of light is related to the indices of refraction of the media involved.
- In mediums that have a greater index of refraction the speed of light is less.
- Formulate the relationship between the index of refraction and the speed of light
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- Nothing can move faster than the speed of light (we shall denote the value of the speed of light as $c$)
- The Principle of Invariant Light Speed: All observers, moving at constant speed, measure the same speed of light regardless of how fast they are moving.
- One of the twins goes on a journey into space in a rocket that has a velocity near the speed of light.
- The speed of light is:
- A stationary observer will measure the same speed of light as an observer who is moving in a rocket ship even if that rocket is moving close to light speed.
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- Special relativity is based on Einstein's two postulates: the Principle of Relativity and the Principle of Invariant Light Speed.
- The Principle of Invariant Light Speed: The speed of light c is a constant, independent of the relative motion of the source and observer.
- The laws of electricity and magnetism predict that light travels at c = 2.998×108 m/s in a vacuum, but they do not specify the frame of reference in which light has this speed.
- Physicists assumed that there exists a stationary medium for the propagation of light, which they called "luminiferous aether. " In 1887, Michelson and Morley attempted to detect the relative motion of the Earth through the stationary luminiferous aether, but their negative results implied the speed of light c is independent of the motion of the source relative to the observer.
- What would be the speed of light from the laser pointer for a stationary observer on the ground?
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- Length contraction arises due to the fact that the speed of light in a vacuum is constant in any frame of reference.
- where c is the speed of light .
- As the magnitude of the velocity approaches the speed of light, the effect becomes dominant.The mathematical formula for length contraction is:
- An observer at rest viewing an object traveling very close to the speed of light would observe the length of the object in the direction of motion as very close to zero.
- Observed length of an object at rest and at different speeds