What exactly is Light Energy?

Question

I know that it is energy that gives off light, but how does it give off light?

Answer 1

Light energy is a variable. The E = hf concept demonstrates that as the frequency of a single photon increases in a given length, the energy becomes greater in proportion to that frequency increase. Photons with long frequencies (radio waves) have very little energy. Cosmic radiation (very short frequency) has a great deal of energy, and is able to damage individual body cells.

The light energy we are able to see indicates the temperature/energy within a particular mass. As energy is forthcoming to a mass, that mass must transmit the energy in some manner or continue to heat up. Red light coming from a mass indicates less energy than white.

Electrons, and their equivalent frequency, passing through a tungsten filament in a light bulb meet with a lot of Resistance due to the size of the filament and the pressure of the voltage pushing against it. Photons (light) energy is a release of the continual forthcoming energy. It is like a person using a sprinkler hose that has many holes the length of it. If the end of it were open so that water could just pass through it, there would be nothing but seepage along the length of the hose. But, if the end is closed up so that pressure builds within it, water begins coming out the small holes the length of it in order to relieve the pressure. The greater the pressure on the hose (the pressure here being compared to voltage) the greater the force/energy.

Answer 2

We call it light energy only because we can "see" it. The light energy is carried but tiny discreet packets of energy called photons that vary in wavelength and amount of energy that we discern as different colors. Light energy is similar to radio waves, microwaves, X-rays and gamma rays as well as ultraviolet and infrared waves that we can not see but all of which travel at the speed of light (it takes about eight minutes for light to travel to earth from the sun!). We call it light energy because when it enters the human eye it reacts with chemical pigments within the cones of the retinal to produce electrical signals to the brain that we can interpret as sight. Hope that helps a little.

Answer 3

Actually, light energy usually refers to the amount of energy contained in the light itself. This, in turn, is a function of the light intensity and wavelength.

It's a fairly complicated subject, but you might try some of the Physics sites on the Web.


Doug

Answer 4

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. The elementary particle that defines light is the photon. The three basic dimensions of light (i.e., all electromagnetic radiation) are:

Intensity (or amplitude), which is related to the human perception of brightness of the light,
Frequency (or wavelength), perceived by humans as the color of the light, and
Polarization (or 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.

Visible electromagnetic radiation
Main article: Visible spectrum
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. There are no exact bounds to the visible spectrum; a typical human eye will respond to wavelengths from 400 to 700 nm, although some people may be able to perceive wavelengths from 380 to 780 nm. A light-adapted eye typically has its maximum sensitivity at around 555 nm, in the green region of the optical spectrum (see: luminosity function). The spectrum does not, however, contain all the colors that the human eyes and brain can distinguish. Brown and pink are absent, for example. See Color to understand why.

The optical spectrum includes not only visible light, but also infrared and ultraviolet.


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for complete info... seee...
http://en.wikipedia.org/wiki/Light

Answer 5

First of all light is said to have dual character that is it has both wave and particle character. light is believed to be made up of particles called photons and the energy posses ed by a photon is given by E=hv

where h = plank's constant
E = Energy of photon
v = frequency of light
you might be wondering if light is made of particles then it must penetrate through our skin and body but actually light particles(photons) have zero rest mass. from above the energy poss ed by light is a definite quantum of energy and it was proposed by max plank and the particle nature of light started from Einstein's photo electric equation
one must have good grasp over dual nature of matter to understand it more clearly. just because of this photon's light appears but it might be a little abstract

Answer 6

when the energy from the sun is released on the outer space,it is traveling at lightyears speed so it arrive the earth easily.but only the good light energy are allowed to enter the atmosphere through the ozone,while the harmful ones are rejected like ultrviolet rays.but it starts when the helium & other gaseous elements combine,forming hydrogen which is the fuel of the sun.then the rest is history

Answer 7

Energy can't be created or destroyed, it just changes form in the form of light, or heat. A law of physics, this can be proven by lighting a fire cracker. Potential energy is ignited (excited) and is transformed into light, and heat energy, "BANG", and it's a flash of light, and heat energy.