0
The speed of light (and all other forms of electromagnetic radiation) in vacuum is determined by
the electrostatic permittivity (ε0) and magnetic permeability (μ0) of free space.
An interesting thought ... we have no way of knowing whether these physical constants are the same
numbers today that they have always been. If either of them has changed since the birth of the universe,
then the speed of light changed, and our observations of the earliest cosmos give an erroneous number
for the age of the universe.
But anyway, that's what these quantities are today, and they're what determines the speed of light,
as is so neatly predicted by Maxwell's equations and verified spot-on by the best measurements.
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How can the nature of the source of light wave can influence the speed of light in a vacuum?
The speed of light in a vacuum is constant at about 3 x 10^8 meters per second. The nature of the source of the light wave does not directly influence the speed of light in a vacuum. The speed of light is determined by physical constants in the vacuum, such as the permeability and permittivity of free space.
What happens to frequency does the speed of light ever change?
The speed of light IN A VACUUM is always the same. In substances other than the vacuum, the speed of light is usually slower than in a vacuum.
What percentage of the speed of light in vacuum is the speed of light in water?
The speed of light in water is about 75% of the speed of light in a vacuum. This is due to the higher refractive index of water, which slows down the speed of light as it passes through the medium.
Is speed of light uniform or not?
The speed of light in a vacuum is constant everywhere. The speed of light in a particular medium depends on what the medium is. It moves slower in air than in a vacuum, and slower in water than in air.
What is the Speed of light travelling through transparent material?
The speed of light when traveling through transparent materials is slower than in a vacuum. This is due to interactions with the atoms within the material. The speed of light is determined by the refractive index of the material, which is a measure of how much the speed is reduced compared to a vacuum.
