what is light?

Answer 1

light is a form of electromagnetic radiation which gives the sensation of sight. refer to a textbook to get other properties.

Answer 2

Answer: By Rinkey


There are several ways to think of light. The classical description
says light is an electro-magnetic wave. This means that it is a varying
electric and magnetic field, which spreads out or propagates from one
place to another. It is not a physical substance. The modern quantum
mechanical description says that light can also be considered to be
particles called photons. These carry energy and momentum but have no mass.
In both descriptions, the light energy is carried by a very real and
observable mechanism. But I would not call it a physical substance.

Answer 3

There are several ways to think of light. The classical description
says light is an electro-magnetic wave. This means that it is a varying
electric and magnetic field, which spreads out or propagates from one
place to another. It is not a physical substance. The modern quantum
mechanical description says that light can also be considered to be
particles called photons. These carry energy and momentum but have no mass.
In both descriptions, the light energy is carried by a very real and
observable mechanism. But I would not call it a physical substance.

Answer 4

Light



Light exists along a relatively narrow bandwidth of the electromagnetic spectrum, and the region of visible light is more narrow still. Yet, within that realm are an almost infinite array of hues that quite literally give color to the entire world of human experience. Light, of course, is more than color: it is energy, which travels at incredible speeds throughout the universe. From prehistoric times, humans harnessed light's power through fire, and later, through the invention of illumination devices such as candles and gas lamps. In the late nineteenth century, the first electric-powered forms of light were invented, which created a revolution in human existence. Today, the power of lasers, highly focused beams of high-intensity light, make possible a number of technologies used in everything from surgery to entertainment.

Answer 5

Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength[1]. The elementary particle that defines light is the photon. The three basic dimensions of light (i.e., all electromagnetic radiation) are:

Intensity, or alternatively amplitude, which is related to the perception of brightness of the light,
Frequency, or alternatively wavelength, perceived by humans as the color of the light, and
Polarization (angle of vibration), which is only weakly perceptible by humans under ordinary circumstances.
Due to the wave-particle duality of matter, light simultaneously exhibits properties of both waves and particles. The precise nature of light is one of the key questions of modern physics.

Answer 6

Light is a spacial vortex.
An electro-magnetic photon that was preceded by all fundamental particles even hydrogen.
The first RF emerged during the evolution of the first stars.
As the star's core approached the fusion point,higher and higher frequencies were produced,RF,IR then visible [to us] light.
Photons are vortexes of energy that must remain in an accelerated state to exist.
Light is easily blocked,absorbed or reflected.
One of the parameters of their existence is the speed "C"
"C" is an absolute in that it is an incident that occurs for the smallest span of time that can exist.

Answer 7

Light is the combination of an electric field and a magnetc field, orthogonal each to other. That's an electromagnetic wave, as x-rays, microwaves etc. These types of waves have different wavelenghts, or frequency (the inverse of wavelenght): our eyes are able to detect only certain frequencies, that we call "visible light" or simply light. For example, parrots can see ultraviolet frequencies; cats can see a more restricted band of frequencies, and they see all "greenish"

Answer 8

It's a form of electromagnetic radiation. Light is in the form of wave-particle duality - which means it is both a particle AND a wave. In it's particle form, the smallest unit of light is a photon, and it carries energy and momentum, but classically no mass. In it's wave form, it has both a wavelength and frequency. Light in the wavelengths 400 - 700 nm is visible light, lower wavelengths are ultraviolet, x-rays, and gamma rays, and higher wavelengths are infrared, microwave, and radio waves.

Answer 9

it is actually a stream of fast moving particles called photons. photons are emitted by any source emitting light. The move in vaccum with the speed of light i.e 3*10^8 m/s

If u reqire further info on how photons are emitted contact me on [e-mail]

Answer 10

The lumens given out by SUN ,the lamp of MOTHER NATURE ,and to a lesser extent by man made sources like incandescent lamps or other such places where one source/ type of energy is converted/transformed in to another source/ type,by some kind of a reaction taking place in the process of conversion.

Answer 11

Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength[1]. The elementary particle that defines light is the photon. The three basic dimensions of light (i.e., all electromagnetic radiation) are:

-Intensity, or alternatively amplitude, which is related to the perception of brightness of the light,
-Frequency, or alternatively wavelength, perceived by humans as the color of the light, and
-Polarization (angle of vibration), which is only weakly perceptible by humans under ordinary circumstances.

Due to the wave-particle duality of matter, light simultaneously exhibits properties of both waves and particles. The precise nature of light is one of the key questions of modern physics.

Speed of light-

The speed of light in a vacuum is exactly 299,792,458 meters per second (fixed by definition). Although some people speak of the "velocity of light", the word velocity is usually reserved for vector quantities, which have a direction.

The speed of light has been measured many times, by many physicists. The best early measurement in Europe is by Ole Rømer, a Danish physicist, in 1676. By observing the motions of Jupiter and one of its moons, Io, with a telescope, and noting discrepancies in the apparent period of Io's orbit, Rømer calculated that light takes about 18 minutes to traverse the diameter of Earth's orbit. If he had known the diameter of the orbit in kilometres (which he did not) he would have deduced a speed of 227,000 kilometres per second.

The first successful measurement of the speed of light in Europe using an earthbound apparatus was carried out by Hippolyte Fizeau in 1849. Fizeau directed a beam of light at a mirror several thousand meters away, and placed a rotating cog wheel in the path of the beam from the source to the mirror and back again. At a certain rate of rotation, the beam could pass through one gap in the wheel on the way out and the next gap on the way back. Knowing the distance to the mirror, the number of teeth on the wheel, and the rate of rotation, Fizeau measured the speed of light as 313,000 kilometres per second.

Léon Foucault used rotating mirrors to obtain a value of 298,000 km/s (about 185,000 miles/s) in 1862. Albert A. Michelson conducted experiments on the speed of light from 1877 until his death in 1931. He refined Foucault's results in 1926 using improved rotating mirrors to measure the time it took light to make a round trip from Mt. Wilson to Mt. San Antonio in California. The precise measurements yielded a speed of 186,285 mi/s (299,796 km/s). This was close to the actual measurement of 186,282.397 miles per second. In daily use, the figures are rounded off to 300,000 km/s and 186,000 miles/s)..