is the speed of light?

Question

a scientific law, theory or hypothosis

but do we know the actual speed

Answer 1

the speed is a definition of c, and has been established as exactly 186,282.397 miles per second. The first truly precise measurement of the speed of light was in 1926, but there were earlier experiments which got the value close. Its fact, but remember this unit of measurement, c, is the speed of light in a vacuum. the speed varies depending on the medium is passes through. For example the light from the interior of the Sun takes around 200,000 years to get to the surface because of the incredibly density of the Sun slow the photons down to a crawl. As soon as it hits the surface and enters the vacuum however, the speed increases back to 186,282.397 miles/s.

Answer 2

It is both a measured value and a theoretically calculated value.

The speed of light has been measured by timing how long it takes a flash of light to return from a distant mirror. It is not an easy experiment because the flash returns in much less than a second even from a mirror many kilometers distant, but it can be done.

Theoretically, Maxwell calculated that disturbances in electromagnetic fields should travel out from a source at 300,000 kilometers per second. He calculated this from easily measured electric and magnetic properties that have nothing to do with light at all. When his calculated speed turned out to be the same as that of light as measured by the distant mirror experiments, he concluded that light is an electromagnetic wave.

Answer 3

The speed of light is a scientific fact. It is the speed at which light travels from one point in the universe (or solar system) to another point. There are various equations to figure out exactly how far points are set apart. For Example; It can take many Earth Years to actually first see the light form a new star. The stars we see every night are always there, you just can not see them during the day because our own sun is brighter than their distant light. If you look at a star at night, that light has actually taken years (sometimes 100's of years) to reach earth. We can formulate how many Earth Years it would take to travel to distant points, but it is easier to convert to Light Years (The Number of Earth years the light has taken to reach us.) If you are asking is it possible to travel faster than the speed of light e=mc2 as proposed by Albert Einstein...That is a very different discussion.
Hope this helps.

Answer 4

Light travels at exactly 186,000 miles per second. It was proved by the Army Core of Engineers just after WW2. By setting up a rotating mirror on Mount Wilson,and shooting a very powerful beam of light from I think San Gorgoneo Mountain, where also a stationary mirror was, and using mathematics with a base line, they were able to calculate how fast the light traveled from one mirror to the next rotating mirror and back. BTW..If you live in the Inland Empire in So. Cal. And are familiar with Baseline Avenue, that's how it got its name.

Answer 5

the speed of light is a scientific law.

Answer 6

It is a phenomenon. There are theories and laws regarding the speed of light, but it is a phenomena in and of itself.

Answer 7

It is a scientific law. In our understanding of science.

Answer 8

The speed of light is a measured physical constant independent of what reference frame it is measured in.

Answer 9

A constant,measure of distance.

Answer 10

It is a constant, like pi, or the charge on an electron.