explain pros and cones of radiation?
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Pros: Alpha radiation sources can be used as power sources in things like pace makers and I think they are also used in smoke detectors. Also it can be used to kill cancer cells.\n\nCons: radiation can kill people or make them very ill. Can cause people to loose hair and become infertile.
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Very high levels of radiation will vaporize people.  High levels burn.  Medium levels cause changes in DNA, cancer, etc.  Low levels just tan you or keep you warm.
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1) Generally, rays of the sun which is called radiation lay between 400 nm (nano meter) to 700 nm.\n2) Below 400 nm is called ultra-violet and above 700 nm is called Infra-red.\n3) Both are invisible to the human naked eye.\n4)Infrared radiation is used to obtain pictures of distant objects and the detection of infrared radiation is used by astronomers to observe stars and nebulae.
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Dark animal fur. Black surfaces are both good absorbers and good emitters of infra-red radiation.
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I hope you don't take this to be something of a cop-out answer. Light is itself an electromagnetic field that is carrying energy through space -- commonly called an electromagnetic wave or 'light'. It is this wave that really makes things visible.\n\nConversely, if you have no electromagnetic wave or one of an invisible wavelength, (at least to the human eye) then it won't bounce off of the object or if it does it won't be visible when it reaches you.\n\nThe visible properties of an object are determined by how EM waves interact with the electrons near the surface of an object. These interactions are what make shiny things shiny (for instance).
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As mechanical engineer this is out of my normal field but felt you deserved an answer of some sort.\n\n"Because of diffraction effects caused by slits or apertures in optical measurement systems, the radiation energy which is directed towards a particular region on a sample will be spread over a larger area than desirable. By employing an apodizing filter in the radiation path in such system, diffraction tails of the system will be reduced. The apodizing filter preferably has a pattern of alternating high transmittance areas and substantially opaque areas where the locally averaged transmittance function is an apodizing function. In the preferred embodiment, the locally averaged transmittance function varies smoothly and monotonically from the periphery to the center of the filter"\n\nI see the theory here, also found on on using an apodizing mirror to stabalise images in a telescope\n\n"I built and used an apodizing screen for my 6" f/8 scope many years \nago. I made it by layering several layers of window screen, each one \nwith a circular cutout of different diameter. The result was an aperture \nmask with a step-wise approximation to a smooth apodizing function. It \nwas claimed to improve contrast for planetary viewing. Anyway, my \nexperience was that it seemed to make the image more stable but if it \nimproved contrast, I couldn't see it. If you do this on-axis, the \ndownside is that your diagonal mirror will now become more of a factor \nin the contrast equation. The bottom line is I wouldn't recommend it."\n\nAlso "An excellent reference for all sorts of technical techniques is\n>"Procedures in Experimental Physics" (also printed under the title\n>"Physical Laboratory Practice") by John Strong.  I don't recall the\n>publisher, but it came out in the 30's.  The bad news it that it's been\n>out of print for decades (and some SOB stole the copy I got from my\n>father!); the good news is that an outfit called Lindsay is reprinting it\n>in paperback.  (Don't have their name/address here in the office; I'll try\n>to remember to look it up tonight.)\n>\n>                            Dr. Kurt Hillig\n\nEvery ATM should have a copy of this great book. Lots of stuff on\nmirror making, figuring, special laps,making flats, prism ,etc.\nThere is nice modifed Draper machine ( upper disk also powered)\nand a homemade diamond cutting wheel to cut small glass blocks.\n( I would like to build this one someday ) A great section on\nkinematical mechanical construction. Yeah this a mid 30,s book but the \ninfo\nstill can be used. No I don't work for Lindsay Publications,<G>\n\nBob Pfaff\n\n\n This book, in paperback form, can be ordered from\n      http://www.amazon.com, on the Web. It can also be ordered\n      through your local bookstore. Amazon prices it at $23.95, and\n      provides the following information:\n\n      Published by Lindsey Publications\n      Publication date: June 1986\n      ISBN: 0917914562"\n\nSorry couldn't find any really decent expplanations, but at least you've got a starting point.
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first of all lets define radiation.\nradiation is the emission of waves or wave travel.\na wave comprises of wave lenths\n1 wave lenth is 1 crest and 1 trough\nwhat are the different types of waves\nthere are two main types\nfirst is the non-ionizing radiation or harmless\nand second is the ionizing radiation or harmful\nplease refer to an electromagnetic spectrum in where it is indicated in detail\nfrom non-ionizing:\nlong waves, radio waves,microwaves, infra-red, visible/white light\n to ionizing:\nUV, x-rays and gamma rays.\nThree main types of ionizing radiation\n1. alpha rays - highly ionizing weakly penetrating\n2. beta rays - med ionizing med penetrating\n3. gamma rays/x-rays - highly penetrating weakly ionizing\n\nso radiation from a blast could be light, and heat but if you use a nuclear bomb there will be ionizing radiation that will affect people and living things.\n\nthe difference between a bomb and a nuclear bomb or dirty bomb is that inside a bomb there are/is radioactive sources like Po, U, Fe and other radioactive sources.\n\nhow does it harm us. you cannot feel ionizing radiation. no human senses can detect them. only specialized equipment do like a geiger counter. ionizing radiation can alter DNA. so if you are affected by large dose, some of your cells will die and alter your DNA.\n\nprotect..?\n\nby using the Time Distance and Shielding concept\nless time you are expose less effect on your body\nradiation reduces its effect by 1/4 every 1 meter\nyou can shield yourself to radiation by knowing what radiatioactive source you are being exposed.\nalpha ray can be blocked by our own dead layer of the skin or paper\nbeta could be blocked by much denser material like book, water, aluminum, glass\ngamma could be blocked by a thick concrete or lead\n\nPM is you have more question
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I'm very interested in becoming an radiology technologist, and from what I've heard, nowadays, the equipment is so good and improved that techs recieve little or no radiation.  There are actually little pins that techs can wear to track how much radiation they are exposed to, and like I said, with the new equipment, the pins have been very helpful in confirming the lack of exposure.
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http://en.wikipedia.org/wiki/Gamma_rays\nhttp://en.wikipedia.org/wiki/Alpha_ray\nhttp://en.wikipedia.org/wiki/Beta_rays\n\nGamma rays or gamma-ray photons (denoted as γ) are forms of electromagnetic radiation or light emissions of a specific frequency produced from sub-atomic particle interaction, such as electron-positron annihilation and radioactive decay; most usually generated from nuclear reactions occurring within the interstellar medium of space.\n\nbeta and alpha are forms of decayed atomic particle. however alpha is the least dangerous form and gamma the most dangerous form. visit the page for extra information
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I assume they want to know about nuclear radiation.  Some basic facts:\n- 3 types are alpha, beta and gamma\n- All are found in nature, you carry it around in you, it comes from just about all natural materials to some small degree.\n- Naturally occuring radiation is little to worry about, we evolved with it and our bodies can handle it.\n- In most areas of the world, natually occuring radiation hits each square inch of your body between 12-18 times per minute!  Radiation can not be felt by the body.\n- Alpha is the biggest particle (nucleaus of a helium atom) and moves slowly.  Not enough speed to even penetrate the layer of normal dead skin on your body.  \n- Beta is an electron moving at higher speeds.  It too is motly blocked by skin, but in high dosages can start to become a problem.\n- Gamma is not a particle, but a wave like light (but much higher frequency).  X-rays and cosmic rays are the best known.  Cosmic rays are the most common type of radiation that hit our bodies per above.  It comes from high speed particles interacting with our atmosphere.  \n- The small amounts of natural radiation we encounter everyday is not a significant problem, but concentrated sources of radiation are.  These have historically included x-rays, byproducts of nuclear bombs or reactors, mishandled medical/agricultural/engineering equipment.  \n- Ingested alpha and beta emitting materials are dangerous even in tiny amounts and can cause cancer.
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A pattern of dark lines or bands superimposed on a continuous spectrum. When a continuous spectrum of radiation (a broad range of wavelengths) passes through a material medium (for example, a cool, low-pressure gas), selective absorption occurs at certain particular wavelengths. This gives rise to a series of dips in intensity (absorption lines) which, in the visible region of the spectrum, appear as dark lines against the bright background of the ‘rainbow’ band of colors that comprises the continuous spectrum. Photons of electromagnetic radiation may be absorbed through radiative excitation, a process that occurs when an electron in one of the lower energy levels of an atom or ion absorbs a photon with energy precisely equal to the difference in energy between that level and one of the higher permitted levels and, as a result, jumps (makes an ‘upward transition’) from the lower to the higher level. Because the energy of a photon is inversely proportional to wavelength, the larger the energy gap, the shorter the wavelength of the radiation that is absorbed when an electron makes a particular transition. An electron does not normally remain in an excited level for long (typically 10−8 s). When it drops down again, it emits a photon or photons that may or may not have the same wavelength as the one that was originally absorbed (depending on whether it drops directly to its original level or descends in a series of smaller steps). If it drops in a series of steps, each of which corresponds to the emission of a photon of lower energy (and longer wavelength) than the one thatwasoriginally absorbed, the total number of photons of the original energy will be reduced and the spectrum will be depleted at the input wavelength. Furthermore, although all the input photons were traveling along essentially the same direction (from the source to the observer), the re-emitted photons travel away in random directions. Consequently, far fewer photons at the absorption wavelength reach the observer than photons of other wavelengths. The resulting absorption line is darker than the adjacent part of the continuous spectrum but, because some photons of that wavelength do reach the observer, not totally black.\nBecause each permitted transition corresponds to absorbing light of one particular wavelength, atoms or ions of a particular element produce absorption lines at a number of different wavelengths, each chemical element having its own distinctive ‘fingerprint’ pattern of absorption lines. The shortest-wavelength lines correspond to the largest energy gaps (i.e. to transitions from the lowest, or ‘ground’, level of the atom or ion). If an electron absorbs a photon with energy in excess of the ionization energy (or ‘ionization potential’), it will be removed from the atom. The absorption spectrum of a particular species of atom consists of several series of lines, corresponding to the various permitted transitions, the short-wavelength limit of the series corresponding to the photon energies above which ionization takes place. Because ionizing photons can, in principle, have any value of energy above the ionization energy, absorption can take place over a continuous range of wavelengths, shorter than the series limit. Absorption of this kind is called an absorption continuum. The prominence (‘strength’) of any particular line depends on the number of atoms of the appropriate chemical element that have electrons residing in the energy level from which the relevant upward transition takes place (the degree of excitation). That, in turn, depends on the abundance of the particular chemical element (the relative proportion of that element in the absorbing substance) and on a number of other factors, in particular the temperature (the higher the temperature, the greater the proportion of electrons in excited states).\nIn addition to producing absorption through electronic transitions (like atoms and ions), molecules may also a
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Every object that has a temperature above absolute zero emits  radiation.  When the radiation comes from a hot object, like the sun, it shows up as visible light or ultraviolet light.  When the radiation comes from a (relatively) cool object, like the earth, the radiation shows up as infrared light (or heat, as we also call it).\n\nThe infrared satellite measures the infrared radiation (that is, the temperature) of what it "sees", which could be the temperature of the cloud tops or, if the sky is clear, the temperature of the ground or sea.\n\nOn infrared satellite images, different temperatures are represented by different colors or different shades of gray.\n\nInfrared satellite images are very useful.  Unlike visible satellite images (that are essentially regular photographs, which means they depend on daylight), they are useful during both day and night!
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HAHAHAH ARE YOU TRYING TO TEST US?\n\nLight is a form of electromagnetic radiation: i.e. it has oscillating electric(E) and magnetic(B) fields that travel through  space at speed c with the same frequency and wavelength.\nrotational energy of light if I am not worng...I like that sh.t!!good question\nRotational energy level gaps typically\n\n \n\nDE = 10^-23 J\n\nTherefore n = 1.5 x 10^10 s^-1
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The incident ray is perpendicular to the surface of reflection.\nThen one has the least distance case.
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Three basic concepts apply to all types of ionizing radiation. When we develop regulations or standards that limit how much radiation a person can receive in a particular situation, we consider how these concepts might affect a person's exposure.  \n\nTime \nThe amount of radiation exposure increases and decreases with the time people spend near the source of radiation. \n\nIn general, we think of the exposure time as how long a person is near radioactive material. It's easy to understand how to minimize the time for external (direct) exposure. Gamma and x-rays are the primary concern for external exposure.\n\nHowever, if radioactive material gets inside your body, you can't move away from it. You have to wait until it decays or until your body can eliminate it. When this happens, the biological half-life of the radionuclide controls the time of exposure. Biological half-life is the amount of time it takes the body to eliminate one half of the radionuclide initially present. Alpha and beta particles are the main concern for internal exposure. \n\nDistance   \nThe farther away people are from a radiation source, the less their exposure. \nHow close to a source of radiation can you be without getting a high exposure? It depends on the energy of the radiation and the size (or activity) of the source. Distance is a prime concern when dealing with gamma rays, because they can travel long distances. Alpha and beta particles don't have enough energy to travel very far. \nAs a rule, if you double the distance, you reduce the exposure by a factor of four.  Halving the distance, increases the exposure by a factor of four.\n\nThe greater the shielding around a radiation source, the smaller the exposure. \n\nShielding simply means having something that will absorb radiation between you and the source of the radiation (but using another person to absorb the radiation doesn't count as shielding). The amount of shielding required to protect against different kinds of radiation depends on how much energy they have. \n\n \n(Alpha)\n\n A thin piece of light material, such as paper, or even the dead cells in the outer layer of human skin provides adequate shielding because alpha particles can't penetrate it. However, living tissue inside body, offers no protection against inhaled or ingested alpha emitters.\n    \n \n(Beta)\n\n Additional covering, for example heavy clothing, is necessary to protect against beta-emitters. Some beta particles can penetrate and burn the skin.\n   \n \n(Gamma) \n Thick, dense shielding, such as lead, is necessary to protect against gamma rays. The higher the energy of the gamma ray, the thicker the lead must be. X-rays pose a similar challenge, so x-ray technicians often give patients receiving medical or dental X-rays a lead apron to cover other parts of their body. \n\nSo in short the lead or other materials absorb the radiation vs. it being absorbed by your body.
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Pros = advantages, benefits, positive aspects of....\n\nCons = negatives, disadvantages, problems resulting from..
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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.