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Speed of Light
Denoted with the symbol "c," the speed of light is 299,792,458 metres per second and is often rounded as 300,000 kilometres per second or 186,000 miles per second.
1,290 Questions
All electromagnetic radiation can travel thought empty space and travels at the same speed?
Yes, all electromagnetic radiation, including visible light, radio waves, and X-rays, can travel through empty space (a vacuum). In a vacuum, all forms of electromagnetic radiation travel at the speed of light, which is approximately 299,792 kilometers per second (186,282 miles per second).
- The incident ray, the refracted ray and the normal to the surface at the point of incidence all lie in one plane.
- For any two given pair of media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant.
- The above law is called Snell's law after the scientist Willebrod Snellius who first formulated it
Thus
Where m is the refractive index of the second medium with respect to the first medium.
for e.g.
the refractive index of glass with respect to air is given as
ratio of -speed of light in air to speed of light in glass.(when light passes from air to glass)
Why doesn't a hollow Prism disperse light?
Infinitely thin walls will not affect the beams of light, if the prism walls are not infinitely thin then there will be dispersion but not much.
What are the modern uses and applications of refraction?
Refraction is the change in direction of a wave due to a change in its speed. This is most commonly seen when a wave passes from one medium to another. Refraction of light is the most commonly seen example, but any type of wave can refract when it interacts with a medium, for example when sound waves pass from one medium into another or when water waves move into water of a different depth.
A medium with a higher index of refraction, like diamond, is more dense than the medium with a lower index of refraction, like air. If the ray of light is moving from the less dense medium (lower index of refraction), to a more dense (higher index of refraction) the ray of light bends TOWARDS the normal.
What are at least two differences between ultraviolet rays and microwaves?
Microwaves are electromagnetic radiation with frequencies in the range from 300 MHz (0.3 GHz) to 300 GHz although some sources restrict their definition to the 3 GHz to 300 GHz range.
Ultraviolet rays are electromagnetic radiation with wavelengths in the range from 10 nm to 400 nm (frequencies from 2.99x107 to 7.5x105 GHz)
Clearly the frequencies are quite different.
Also - since the frequencies are so different, UV filters may not filter microwaves and vice-versa. Sunblock may protect you from getting a sunburn from UV rays but it won't block microwaves at all. Similarly, absorption of the two forms of radiation is quite different. Microwaves can heat a cup of soup up very nicely while you could die of starvation waiting for UV rays to heat it up.
Does the wavelength and frequency of light changes when it enters glass from air?
Nothing. The speed changes. We live in a universe where electromagnetic waves change frequency if they can't change speed (and in a vacuum they can't), and only change speed if they enter another medium like glass.
Does a microscope form a real image?
Actually, the image doesn't form in the microscope. The image forms on your retinas. The microscope focuses light in such a way that it comes together correctly on your retinas.
How many times is speed of light compared to sound?
The speed of sound is the velocity of sound through a mechanical (elastic) medium. And the difference is between the speed of sound and light is that Light travel faster then the sound.
Light traveling through vacuum is roughly 879 thousand times
faster than sound traveling through air at sea level.
What is the index of refraction (n)?
The prism is an optical device which offers different refractive index for different colours. If we take the case of white light which consists of "VIBGYOR". The red light will have less refractive index when compared to Violet or Blue colurs. The refractive index depends on the wavelength of the incident wave. If the wavelength is more , refactive index is less and vice versa.
Uma
What happens when speed of light enters a new kind of medium?
When light passes from one medium to another with a different refractive index, and
not in a direction perpendicular to the boundary between the media, its speed changes.
Do gamma waves travel at the speed of light?
I don't quite understand what this is referring to, but no.
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Nobody knows whether the universe moves or not.
When light travels from air into glass the wave speed?
Its speed would decrease upon moving from a less dense to a more dense medium
What is speed of light in miles per year?
It is the same speed all year. If you meant to ask: "How far does the speed of light go in a year?" The Answer is: about 6 trillion miles.
EDIT:
Light travels 9.454.254.955.488 kilometers per year which translates to 5.874.601.673.407 miles per year.
That's about 9.5 trillion kilometers or about 5.9 trillion miles.
This distance is called a light-year.
Why does a light ray travel slower through a glass block?
When light enters certain materials like glass or water it is absorbed by the atoms and molecules in the material as energy. These energized atoms and molecules then give up their energy by emitting light. The whole process is actually very complicated but the absorption and reemittance process effectively slows the progress of the light thru the material.
How can you focus white light?
You can use a concave or vice-versa round glass object AKA magnifiying glass. Then you have to focus the rays' vectors straight through the center of the magnifiying glass so that it focuses light into a single spot.
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 happens to the speed of light as light travels though materials?
The speed of light is not affected by the density of the medium. Its the path of the light that is affected . Phenomenon like reflection or refraction take place when the light goes to different medium
What travels at aproximately 186.000 miles per second?
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The speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second
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yes but when its rounded up and added up or whatever it is 300000 kilometers.
the answer is: Light.
Why a change in speed of light causes refraction of light?
It is only possible if light enters another medium with an angle other then 90.
WHen it does so then some part of light enters the medium first and it slows down first while the other part enter after a while and slows down later. This time gap .For much better understanding see... http://www.youtube.com/watch?v=Tyzci1qTVL8
