What type of EM radiation tans human skin?
138840
Its UV or ultra voilet Radiation
830662
From Wikipedia: "The visible spectrum (or sometimes optical 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."
452427
solar radiation - UV rays are damaging to the DNA of skin cells and can result in cancer
1173968
It is correct that the visible wavelengths of electromagnetic radiation  are from 400nm (violet) to 700nm (red); but that is because of the way the eye perceives light, and has nothing to do with the way waves interact with each other.  Also, because of the way the eye sees color (and not due to the nature of the waves) many colors can be produced either by a  single wavelength of a combination of two or more wavelengths.  For additive color reproduction three primaries are selected (red, blue and green) because they produce the widest range of other colors (gamut), probably because of the way the eye works.  Other primaries can be used, but they will result in a more limited range; also more primaries can be added to increase gamut.  How selected primaries are combined to create other colors is shown in the "CIE color chart".
75779
This is intuitive if you remember that light is an example of an electromagnetic wave.  \n\nA lens can focus electromagnetic waves, and mirrors can divert them.  They can be 'stopped' by being absorbed into something, and many materials will absorb electromagnetic waves (like skin, that absorbs light, and therefore warms up and gets tan in sunlight).
509957
Electromagnetic radiations or waves are propagating in space. Electromagnetic waves have electric and magnetic components, the electric field and the magnetic field oscillate at right angles to each other and to the direction of propagation.\nAs any other waves e.m. waves are characterized with  frequency (number of vibrations in one second), wavelenght (the distance from one crest to the next crest in the sinus wave) and radiant energy. \nThe range of the e.m. waves is called the electromagnetic spectrum. The highest frecvency and energy / the lowest wavelenght e.m. radiations are gamma rays (are shorter than the size of the nucleus in the atom) then X rays, ultraviolet radiations, visible light, infrared radiation (heat radiation), microwaves, and radiowaves which has the lowest frequency and longest wavelenght (can be several km long). We can see only the visible light, the other e.m. radiations are invisible to us. But they can have an effect on our organism. They have a lot of technical, medical and other use.\n\nfor more see >>\nhttp://en.wikipedia.org/wiki/Electromagnetic_radiation
109050
Electromagnetic waves.  That includes x, gamma, visible light etc...\n\nGravitational waves.
118278
Nothing.  Light is a form of radiation, just as are microwaves, radio waves, ultraviolet rays, x-rays and gamma rays.  However, ultraviolet, x-rays, and gamma rays contain much more energy than do light waves, so they can be damaging to biological tissue.
78289
Light energy is a form of electromagnetic radiation and is found in a segment of the (EM) electromagnetic spectrum. \n\nThe EM spectrum encompasses the entire range of ionizing and non-ionizing radiation extending in frequency from approximately 1023 hertz to 0 hertz, or in corresponding wavelengths, from 10-13 centimeter to infinity. \n\nThis spectrum includes all forms of classical non-ionizing radiation we are familiar with including ultraviolet light, VISIBLE LIGHT, infrared (light) radiation, microwaves, and radio waves. The spectrum also includes ionizing radiation such as cosmic-ray photons, gamma rays, x-rays. \n\nAt eithe end of the visible light spectrum is infared and ultraviolet light and humans cannot perceive these spectrums of light.  Red colored light is longer wavelength of light and visible violet light is shorter wavelength.\n\nFor a cool chart and more in depth descriptin of the EM spectrum check out the Goddard Space Center's special page on this topic. \n\nhttp://imagine.gsfc.nasa.gov/docs/science/science.html   Use the link that says The Electromagetic Spectrum
977478
There have been many studies into Radio Frequency (RF) absorption into tissue and whether or not it causes damage.  Cellphones are the biggest target, because they contain a radio transmitter which you hold on or near your head.  The FCC uses a test called SAR (specific absorption rate) to measure radiation absorbtion rates into tissue.    The Wiki entry for SAR:\n\n"SAR is a measure of the rate at which radio frequency (RF) energy is absorbed by the body when exposed to radio-frequency electromagnetic field. The most common use is in relation to cellular telephones. In the United States, the Federal Communications Commission (FCC) has adopted limits for safe exposure to RF energy produced by mobile devices and requires that phones sold in the U.S. have a SAR level at or below 1.6 watts per kilogram (W/kg) taken over a volume of 1 gram of tissue. In the EU the corresponding limit is 2 W/kg taken over a volume of 10 grams."\n\nBluetooth devices, by their very nature, are short-distance radio communication devices, and so will operate at a far lower radio emission level than their cellular cousins.  A study by William G. Scanlon of Queen's University in Belfast found that a typical Ericsson Bluetooth radio module generates a SAR of just 0.001 watts per kilogram, which is well within the safe limits.
978132
Infra-red from either source are the same, the only variable is the wave length. For example U/V from the sun versus U/V from a tanning bulb are identical except that the tanning bulb produces U/V of a known wave length and the sun covers many wave lengths ranging from about 1,500 to 3,000 angstroms or so. Sunlight therefore produces variable wave lengths of Infra-red but the body does not. We use infra-red in medicine to determine areas of heat (infections or to indicate tumors by producing less Infra-red.)
169514
nahhh   it not give u that helthy green glow.     all electonics give off some form of radiation.    but   smaller  eletronics  do not give off alot that can be dangerus
270577
A pulse of energy - electromagnetic radiation. So anything from radio waves to gamma rays counts as electromagnetic radiation. A pulse of this energy is usually associated with nuclear weapons due to the high intensity of radiation emitted by a thermonuclear reaction.
437815
The previous post is pure bunk.\n\nMillions of dollars have been spent and thousands of people have been tracked and interviewed over decades in an attempt to scientifically prove or disprove a link between ill health and electromagnetic fields. And guess what? They can't find one. There is no known biological mechanism for the low-level radiation from power lines to damage DNA. \n\nPeople used to worry about the same things resulting from the use of microwave ovens, but I guess that scare has passed. The low level radiation from power lines is even less than that emitted by microwaves. Radiation from cell phones isn't a health issue, either.\n\nHere's a relevant passage from Christopher Wanjek's "Bad Medicine: Misconceptions and Misuses Revealed, from Distance Healing to Vitamin O":\n\n"Many folks seem to equate all kinds of radiation with the dangerous kind, called ionizing radiation. This type of radiation is energetic enough to knock an electron loose from an atom. Many types of radiation pass through our bodies all the time. Although you cannot shine a flashlight (visible light) through your chest, radio waves and microwaves will pass through easily enough. Ionizing radiation also passes through you, but it can damage the atoms in your cells as it travels, knocking loose an electron from a DNA molecule. Ultraviolet light is ionizing radiation; too much of it causes skin cancer. X rays and gamma rays are also ionizing. Too many X-ray exams can lead to organ cancers. Fortunately, the nastiest forms of ionizing radiation are produced in deep space, and the earth's atmosphere blocks most of this from reaching the earth's surface (although that hole in the ozone layer is letting in more UV). ...Over 80% of the ionizing radiation we encounter day to day comes from natural sources: cosmic rays, which are atomic particles from space; and alpha and beta particles from radioactive gas, namely radon. ...Medical X rays account for about all the rest of our ionizing radiation exposure."\n\nYou don't have to move, and no one's brain is being harmed.
477826
heat is not electromagnetic radiation, it's molecular kinetic energy (or thermal energy).  The sun emits Ultraviolet radiation, amongst other emissions in the light spectra, but i don't believe the heat emitted can be attributed to an electromagnetic wave.
421381
Several Units actually and they can be a bit confusing\n\nRad, Rem, Seiverts, grey, etc etc\n\n\nhere is the break down\n\nKerma = Kinetic Energy transferred to charged particles in Rads / Grays.\nRad = radiation absorbed dose\n= 100 ergs of energy / gm of tissue\n= 0.01 joule of energy / kg of tissue\n1 Gray = 100 Rads = 1 joule of energy / kg of tissue\n1 Rad = 0.01 Gray\n1cGy (centi Gray) = 1 Rad\n1 mGy (milli Gray ) = 0.1 Rad\nRem = radiation equivalent man\n= rad x RBE (QF) / (relative biological effectiveness or Quality factor)\nSeivert = Gray x QF\n1 Seivert = 100 rems \n(1000 milliSv or mSv)\n1 mSv = 0.1 rem ( for Xrays which have a qualifying factor of 1) = 1 mGy\n\n\n\nconfusing huh?  took 2 college terms on it myself
1100040
your funny, i dont know what it is but i dont think its a skin desease, i could be wrong, but i chuckled when i read  your question\n\nok i had to look it up\nhttp://ds9.ssl.berkeley.edu/LWS_GEMS/4/uve.htm\n\nthis may be what you mean... its very sensitive to ultra vilolet light, but they called it children of the moon