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raymes_k
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Why can just about all frequency/wavelength electromagnetic waves penetrate through physical objects (even if only a thin piece of wood or something) but light cant?
raymes_k said:Why can just about all frequency/wavelength electromagnetic waves penetrate through physical objects (even if only a thin piece of wood or something) but light cant?
On one level, the question does not make sense, since light IS an electromagnetic wave.raymes_k said:Why can just about all frequency/wavelength electromagnetic waves penetrate through physical objects (even if only a thin piece of wood or something) but light cant?
LURCH said:Still, the question is, on the whole, valid. For example, in an in it is true that light in the visible spectrum and will pass through glass, and that is why am I can see out the windows of my house. In fact, it is the very fact that the windows are transparent to light in the visible spectrum that makes them an exceptional part of the wall. Yet, if I put my radio in a room with no windows, it will still receive a signal x-rays will pass through the wall, and a person with "heat vision" or "thermal vision" goggles will be able to see me through the wall. The same will hold true for Sheetrock, drywall, plywood, cloth, even (to a lesser degree) stone or brick. A strong enough heat source can be detected by a thermal scope even through a solid slab of concrete. A visible light, no matter how bright, won't. Is it simply coincidence that so many materials in our everyday life are opaque to light in the visible spectrum and translucent/transparent to the majority of the rest of the spectrum?
For organic materials I could see some connection with the fact that organic sells are specifically designed to trap light in the visible spectrum, because that is the spectrum in which our Sun produces the majority of its radiation. But what about the rest? Setting aside metals and crystals, there is still an awful lot of material that fits this description, isn't there?
raymes_k said:first of all - thanks to all the arseholes who picked on the wording of my question - most probably cause its my first post -- doesn't mean I am an idiot. i realize light can penetrate glass (duh) and some other materials but as lurch says, is it merely coincidence that so many materials are opaque to light. the diffraction argument is invalid IMO - although most EM waves (those of lower frequency) cannot pass through a thin sheet of metal, if i were in a room with no windows (as lurch says), i would still receive radio waves. No matter how the radio waves are getting to me, they must be PENETRATING somewhere. the diffraction argument does allow radio waves to be transmitted to places where they would not generally received but its not relevant here
That was going to be my next question. Is that really true, that there are more things that are opaque to visible ligth than vise versa? I mean, it would seem tio make sense, what with the shorter wavelength and all, btu I never heard if it were actually true or not.ZapperZ said:The question I asked in my last posting stand - what's so special about visible light anyway that you have to pick on it? I can find more things that can stop UV and IR but still let visible light pass through.
Zz.
Electromagnetic radiation, or EM radiation, is able to penetrate physical objects due to its unique properties. EM radiation consists of electric and magnetic fields that oscillate perpendicular to each other and travel through space at the speed of light. These fields are able to interact with the atoms and molecules of physical objects, causing them to vibrate and allowing the radiation to pass through.
The ability of EM radiation to penetrate physical objects depends on several factors, including the frequency and wavelength of the radiation, the material and thickness of the object, and the angle at which the radiation approaches the object. Higher frequencies and shorter wavelengths tend to have better penetration abilities, while denser and thicker materials can block or absorb more radiation.
The penetration of EM radiation can vary greatly depending on the type of physical object. For example, non-metallic objects such as wood and plastic generally allow EM radiation to pass through more easily, while metals can reflect or absorb radiation. Additionally, the shape and structure of the object can also affect its ability to block or allow EM radiation to pass through.
No, there are certain physical objects that can completely block the penetration of EM radiation. For example, lead and other dense metals are highly effective at blocking most forms of EM radiation. However, even these objects may allow some radiation to pass through at certain frequencies or angles.
The ability of EM radiation to penetrate physical objects is utilized in various applications, such as medical imaging, security screening, and communication technologies. For example, X-rays use the penetration of EM radiation to create images of bones and tissues in the human body, while airport security scanners use the same principle to detect objects hidden in luggage. Wireless communication technologies also rely on the penetration of EM radiation to transmit signals through physical objects and allow for wireless connectivity.