answersLogoWhite

0

The speed of light (usually denoted c) is a physical constant. Its value is exactly 299,792,458 metres per second, often approximated as 300,000 kilometres per second or 186,000 miles per second. It is the speed of electromagnetic radiation. (such as radio waves, visible light, or gamma rays) in a vacuum, where there are no atoms, molecules, or other types of matter that can slow it down.

The actual speed at which light propagates through transparent materials, such as glass or air, is less than c. The ratio between c and the speed v at which light travels in a material is called the refractive index, n of the material (n = c / v). For example, for visible light the refractive index of glass is typically around 1.5, meaning that light in glass travels at c / 1.5 ≈ 200,000 km/s; the refractive index of air for visible light is about 1.0003, so the speed of light in air is very close to c.

User Avatar

Wiki User

15y ago

What else can I help you with?

Related Questions

What is the cause for the flickering of objects when seen through hot air?

The speed of light changes if the density of medium changes. In hot air, the density is less so due to the change in speed of light, we think that it is flickering.


Which is faster the speed of sound in air or the speed of light in air?

Speed of light in air ~ speed of light in vavuum = 3,00 *10^8 m/s speed of sound in air ~ 330 m/s. Speed of light is faster than sound in air


What needs to travel through the air slowly?

An hot air balloon i think.


Seeming as the speed of sound in air speeds up if the temperature rises therefore how hot would you have to heat the air up until the speed of sound through that air is equal to the speed of light?

It never would. Sound is vibration through some physical medium; the speed of sound is related to the speed of the vibrations. No physical medium can move at the speed of light, so the speed of sound could never get there.


Is the speed of light slower in air or in a vacuum?

Speed of light is max. in vaccum and slower in air.


How do the speed of light and the speed of sound compare through air?

The speed of light is significantly faster than the speed of sound in air. The speed of light in a vacuum is approximately 299,792 kilometers per second while the speed of sound in air is about 343 meters per second. This means that light travels almost a million times faster than sound through air.


How is the speed of light and speed of sound related?

The speed of light is about 900,000 times as fast as the speed of sound in air.


What is the difference in the speed of light in air, water, and glass?

The speed of light is fastest in air, slower in water, and slowest in glass.


Speed of rising hot air?

The speed at which hot air rises depends on various factors such as the temperature difference between the hot air and its surroundings, the density of the air, and any obstacles in its path. Typically, hot air rises at a rate of around 1-3 feet per second.


Why light is refracted as it moves from air into glass?

Light is refracted as it moves from air into glass because the speed of light changes as it travels from a less dense medium (air) to a more dense medium (glass). This change in speed causes the light rays to bend, resulting in refraction.


What is the formula for calculating the air speed of a hot air balloon?

Velocity = Distance/Time for most all movement problems While the above formula is true for most movement problems, air speed is not a velocity. Air speed is speed of an aircraft relative to the surrounding air. The air speed of a hot air balloon is always zero because it is not moving through the air.


Does the speed of light have air in it?

No, the speed of light is a fundamental constant in physics and does not contain air or any other material substance within it. It is the speed at which light travels in a vacuum.