i dont unerstnd the concept of light. what is it? you cant really "see" it, you cant "Feel it" and

Question

it makes things more visible to the human eye. i know its a form of energy, but how does it , and why does it "light up"?
same for light bulb. why do the electrons light up when they face resistance?

Answer 1

light as everything in life is on the 'void'-its there and at the same time is not

Answer 2

Light is electromagnetic radiation. What we see as light is only a small part of the electromagnetic spectrum. Longer wavelengths than red in our spectrum are called infra-red - we can feel this as heat. Visible light is visible to us because the energy in the light causes chemical reactions in the cells on the back of our eyes (the retina) which generate nerve impulses. These impulses go down the optic nerve to our brains where they are interpreted as an image.
In an incandescent light bulb, the light is produced not by the electrons directly, but by the heating up of the filament. This radiates energy as light. In a fluorescent, gas atoms are excited by electrons and release photons of ultraviolet when they return to their ground state. This UV radiation is converted into visible light by a phosphor lining the tube.

Answer 3

The primary source of light is from combustion.Light is a group of photons that behaves both as a particle and a wave.It is an electro-magnetic radiation that comes under the visible spectrum.

Answer 4

Actually, a very good question. Scientists all over the world are asking the same thing. Is light a wave, or is it a photon? Or Both?
The best explanation, in plain English is at:

science.howstuffworks.com/light2.htm

Good for you for thinking! Keep it up!

Answer 5

Light is the opposite of dark. we live in a world of opposites. If you were always in light you would never know what light was/is. You need the dark as you need up in order to experience down. (?)

Answer 6

well! light doesnt help you see better, it is the sole thing that actually makes you see, without it you wouldn't see anything at all. don't look too deeply into it, theres little point!

the electrons get very annoyed and so they light up in anger.

Answer 7

well, think about it the way u think about sound waves, they'r basically almost the same (to us humans at least) u don't 'feel' sound waves, instead when they react with ur nueral cells in ur ear, they form an electric signal that is processed in ur brain as sound...
the same thing goes with light, when it enters the ur eye and reacts with ur nueral cells in ur retina, they form electric signals that ur brain processes as images...

Answer 8

Are you lonely? If I could see you were a person, I'd talk to you.

Answer 9

--Here is brief prospective of light:

*** it-2 p. 253 Light ***

The Hebrew term ´ohr and the Greek term phos refer to that which emanates from a light-giving body such as a lamp (Jer 25:10) or the sun, as well as to the opposite of darkness, literally and figuratively. (Isa 5:20; Joh 11:10, 11) It is generally believed that light consists of energy particles that have wave properties. To this day, however, man still cannot give a complete answer to the question propounded over three millenniums ago by the Creator of light: “Where, now, is the way by which the light distributes itself?”—Job 38:24.

Light from the sun is a combination of colors, with each color having a different wavelength. The color of an object is determined by the particular portion of the light reflected by its surface. Thus light furnishes the many hues that delight the eye of man. It is also essential for earthly life—plant, animal, and human—to continue.

--This is a scientific prospective:

*** g71 6/22 pp. 9-10 Colors—from Light ***

HAVE you attempted to make your way around a pitch-dark room? Or have you ever closed your eyes tightly and tried to go about your daily activities? You may have found it rather frightening. It is a real relief to see the light! The inspired words of the Bible are indeed true, “The light is also sweet, and it is good for the eyes to see the sun.”—Eccl. 11:7.

The sun is our main source of illumination. Every second of every day it is changing four million tons of its matter into energy. This is sprayed out in all directions from its surface at over 186,000 miles a second! But what is the nature of these emissions? How do they make vision possible? And how is it that they enable us to see such a great variety of colors?

What the Sun Gives Out

The emissions from the sun are called “electromagnetic energy” or “radiation.” This radiation is frequently viewed as a stream of tiny particles. But, at the same time, it is also viewed as traveling in waves. Commenting on this apparently contradictory view, Professor Walter J. Moore said: “This unwillingness of light to fit neatly into a single picture frame has been one of the most perplexing problems of natural philosophy.”

While all radiation, including light, travels from the sun at the same speed, it is not all the same. There are many kinds. Some kinds of radiation have very long wavelengths, being measured in miles. Others have very short wavelengths, measured in tiny fractions of millionths even thousand-millionths of an inch.

Radiations that have longer wavelengths include heat waves and the very long radio waves. And among the shorter radiations coming from the sun are ultraviolet rays, X rays, gamma rays and the very short cosmic rays. But none of these are visible to human eyes, and so they are sometimes called invisible light. However, in between the longer heat waves and shorter ultraviolet waves is a very narrow band of wavelengths that are visible. So the part that we see is only a very narrow band in the middle of a broad spectrum of wavelengths, from cosmic rays to radio waves and electrical currents.

Radiations Reaching Earth

Not all radiation the sun sends toward earth reaches here. This is because earth’s atmosphere acts as a shield. Thus what reaches earth are essentially the wavelengths of visible light, with a restricted range of invisible waves. How glad we can be that our atmosphere keeps out most invisible radiation, for if it were permitted to reach earth it would kill us all!

On the other hand, we can be grateful that visible light floods our earth in such abundance. Plants capture the energy from light and employ it in converting carbon dioxide and water into a simple sugar that is the basis of all food. Without this energy from light, plants could not grow, and nothing could live on earth.

Wavelengths That Give Color

But light gives us much more. It blesses us with gorgeous color and beauty. What is so remarkable is that the band of visible wavelengths that give us light and the many colors is so narrow. These wavelengths measure from only about thirty-two millionths of an inch from crest to crest, which our eyes recognize as red, to about sixteen millionths of an inch, which we see as violet!

Traveling at the speed of light, as these rays are, the number of waves striking the eye are between about 375 and 750 million million a second. This vibration the human visual system interprets as light, the color corresponding to the frequency of the vibrations.

Light’s Numerous Colors

Does it seem strange to you that we should speak of light as being composed of different colors? Did you think that it was all white? Well, it usually appears white to our eyes because all the wavelengths of visible radiation are traveling together. They are unseparated. But when the wavelengths are separated, we can see their individual colors.

You might check this for yourself sometime. You can hold a long-playing phonograph record up to the light and look along its finely ridged surface. The light will be diffracted and you can see the light’s various colors. Or you may have observed after a rainstorm how the tiny droplets of water in the air have separated sunlight into its basic colors—violet, blue, green, yellow, orange and red—producing a beautiful rainbow.

This does not mean that light can be separated into only these few colors. It can actually be split into tens of thousands of different wavelengths, each producing a different hue or shade of the basic colors! The eye, however, cannot distinguish between the color of one wave of light and the color of another wave if they are too similar in length.

Studies have revealed that the human eye can distinguish about 128 separate shades of color in visible light. But in order to distinguish even this many, one wavelength of light must be projected on a screen, and before it is removed, another one of a slightly different wavelength must be projected alongside. Only by visually comparing them can the eye tell the difference between more than a hundred colors in visible light.

The Source of All Color

For a moment raise your eyes from the printed page, and look closely at certain things around you—perhaps a bookcase, a desk or even the floor. Is it not amazing what a great variety of color there is? But from where does all the color come?

Color does not exist in the desk, the floor or whatever object at which you may have been looking. True, we may speak of these things as being of a certain color. But the truth is, we do not live in a world of colored objects. The color of things is actually in the light that shines upon them. Light is the only source of color, and without light not even the faintest color exists.

Seeing Light:

But how is it that we can see light with its innumerable wavelengths of color?

Light cannot be seen as it travels through space, any more than can radio waves and other radiation. What causes light to become visible to the eye are the material substances upon which it falls.

For example, if we were in a room without particles of dust or even air, we could not see the beam or path of light from a flashlight if one were turned on. A beam of light in a vacuum is quite invisible. Thus when the astronauts in space looked out their window they could see the brilliant sun, but the sky was black. Black is the absence of light or color. The sun did not light up the sky because space does not have substances upon which the sun’s light can fall. We can see light only when it hits some object that will reflect its waves to our eyes.........

........Producing Color in the Sky
Our sky is filled with air, as well as tiny particles of vapor and dust. Earlier we noted that the atmosphere shields us from deadly radiation. It acts like a giant mirror to reflect most of such radiation back into space. However, light penetrates this shield, but in so doing many of its waves are scattered by the particles of air. The size of these particles is such that the shorter blue waves are scattered far more than others. Thus the sky has a blue color.

But when the sun is near the horizon it can be different. The more horizontal angle of sunlight shining through a dust-laden atmosphere tends to scatter light’s longer waves, causing the sky to take on a deep orange and red appearance. Thus, back in 1883, after the Krakatoa volcano erupted violently and scattered dust particles through earth’s atmosphere, the world enjoyed a series of remarkably beautiful sunrises and sunsets........"