Why does light have a constant velocity

Light is a kind of electromagnetic wave, electromagnetic wave has a constant frequency and wavelength, the wavelength is the length of each wave in the electromagnetic wave, since the wavelength is constant, the speed of light propagation in a certain medium is constant. Light travels at different speeds in different mediums and travels fastest in a vacuum.

Light is pure energy, the effect of change on the surroundings is sequential and transmitted to the distance in the form of waves, and particle nature is the manifestation when it encounters matter. The sequential wave diffusion lays the foundation of time and the limit of the speed of light.

There is a relationship between the speed of light and the medium through which it spreads.

The so-called constant is in a vacuum, and the propagation of waves in the same matter is of course constant.

The speed of light is a constant quantity, and the reason why it is that number is related to how long one meter is.

Everyone didn't understand what the landlord meant, and what he wanted to ask was, why is the speed of light constant relative to any frame of reference?

No one can tell

The speed of light is generally a constant speed of light, and in nature we can find that the speed of the wave (not just the light wave) is obviously constant by our observations.

Since the 20th century, light has become a topic that cannot be avoided by the scientific community, with the speed of light giving birth to the theory of relativity and the motion of photons giving birth to quantum mechanics. What is even more outrageous is that the speed of light is above the entire Newtonian mechanics. Models.

Because, according to Newtonian mechanics, the speed of any matter needs to be preceded by a reference frame, and the corresponding speed can be obtained based on the reference frame, but the speed of light is above any reference frame, and it is a fixed value in any reference frame: 3*10 8m s, which once broke scientists down, which led to a scientific revolution, based on which Einstein proposed the theory of relativity.

Scientists have discovered that any matter is made up of atoms, which in turn are made up of electrons and nuclei, and the nucleus contains protons and neutrons, which in turn are made up of quarks. More than 99% of the mass of matter comes from the strong force of gluon transmission that confines quarks to protons and neutrons.

Specifically, according to Einstein's theory of mass-energy equivalence, energy actually corresponds to mass crack resistance, and gluons bind quarks together by using huge energy, which is equivalent to mass. Therefore, the mass of any substance mainly comes from the part of the energy corresponding to the strong transfer force of gluons.

The medium effect of the speed of light:

The speed of light in different media is different, and since light is an electromagnetic wave, the speed of light also depends on the dielectric constant and magnetic permeability of the medium. In isotropic stationary media, the speed of light is a fixed value less than the speed of light c in a vacuum.

If the medium moves at a certain speed, the general way to find the speed of light is to first establish a follower frame of reference, where the speed of light is the speed of light in the stationary medium, and then obtain the speed of light in the moving medium through the reference frame transformation; Alternatively, the speed of light in a moving medium can be found directly using the relativistic velocity superposition formula.

The speed of light in a vacuum is the oldest physics.

One. It was proposed to travel a kilometer of light to determine its speed, but it was unsuccessful because of the imperfection of the equipment used.

Denmark, 1676.

For the first time, an effective method of measuring the speed of light was proposed—utilization.

of erosion. Huygens according to.

The presented data and the radius of the Earth, for the first time calculated.

The speed is about 200,000 km/s; England, 1728.

The speed of light is 310,000 km/s;

The Frenchman Fisso measured the speed of light at 315,000 kilometers per second; In 1850, the French physicist Foucault measured that the speed of light was 298,000 kilometers per second;

The speed of light measured by Corneon is 299,990 kilometers per second.

Next up is Michael Erson, who has made the speed of light his lifelong goal. Michael graduated in 1873.

college, and stayed on to teach physics and chemistry. About five years later, he began to measure the speed of light, and then traveled to Europe, studying optics in Germany and France. After returning home, he left the Navy to become.

Professor of Physics at the Faculty. Michael Erson, because of precision.

and with the help of these instruments.

and the contribution made by the research work of metrics was obtained in 1907.

Michael Erson himself designed a rotating mirror and an interferometer to determine tiny lengths

and wavelengths of light waves. In 1879, he obtained the speed of light at 299,910 5 km/s; In 1882, he obtained the speed of light at 299853 6 km/s. This result is recognized as an international standard and has been used for 40 years.

Michael Erson's last measurement of the speed of light is in.

Two mountains 35 kilometers apart, measured at the speed of light.

In the end, it reached 299798 4 km s. He had a stroke during this measurement.

Pass away. After the widespread use of lasers, lasers began to be used to measure the speed of light. The method is to measure the frequency and wavelength of the laser, and apply c = to calculate the speed of light c, which is currently the most accurate way to measure the speed of light.

According to the resolution of the 15th International Conference on Weights and Measures in 1975, the value of the speed of light in the vacuum of the finger plum was set as.

c=299,792485±

In the usual application of multi-only masking late fetch c = 3 10 8 m sec.