How fast is speed of light?

Answer 1

It about 2*10^8 m/s.
The speed of light is slower when passing through glass, or any other transparent substance, compared to the speed of light passing through a vacuum. The actual speed depends on the refractive index of the glass, which depends on the composition of the glass.

Answer 2

Different glasses have different indices of refraction, i.e., different speeds of light. The index of refraction - and therefore the speed of light - also typically varies slightly for different wavelengths. A typical value for the speed of light is about 2/3 the speed of light in a vacuum. That is, since the speed of light in a vacuum is 300,000 km/sec., the speed of light in glass would be about 200,000 km/sec.

Answer 3

In Science, the phrase "speed of light" is used to denote the speed with which light, or

any other wavelength of electromagnetic radiation, travels from one place to another.

That is, the distance between the two points, divided by the time required by light to

traverse the distance.

The speed depends on the electrical and magnetic properties of the substance,

or lack thereof, through which the light is traveling. The speed in vacuum is

299,792,458 meters per second ... almost 671 million miles per hour.

Answer 4

The speed of light in a vacuum is approximately 299,792 kilometers per second (or about 186,282 miles per second). It is considered to be the fastest speed at which energy or information can travel in the universe, according to the theory of relativity by Albert Einstein.

Answer 5

the speed of light is currently 0.5 of a killisecond.

Answer 6

As steel is a conductor, electromagnetic radiation and therefore light cannot propagate through it.

There is no such thing as a speed of light through steel.

Answer 7

1484 metres per second in water and 6100 metres per second in steel.

Answer 8

0m/s, iron is opaque to light.