Can radio waves go through walls?
438842
Like light rays radio waves are reflected refracted and diffracted and absorbed by materials. At certain angle of reflection radio waves are also polarized.\n\nSince it is an E.M wave it travels in vacuum or air with velocity C.\n\nThey are reflected by metals, but absorbed by many substances like wall. The absorption depends upon the thickness of the material.Usually the thicknes of a wall is such as to absorb radio waves. \n\nBecause of long wavelength it can bend across obstacles, and even small cleavage in a wall can fill a room with radio waves.
25439
There is some sort of a polymer that blocks 4 Ghz, which is WiFi, and yet allows other frequencies through. \nhttp://www.forcefieldwireless.com/windowshield.html\n\nHere is a company that makes glass that will block cell phone signal frequencies. They also sell the polymenrs with various blocking capacity. \nhttp://www.lessemf.com/plastic.html\n\nNice question. I won't have to smuggle that cell phone jammer back from Europe after all!!!
985973
Actually this is quite possible.  The key is that the laser emits a wavelength which interacts with the N2, O2, and CO2 in the air.  Each of those molecules have specific absorption and emission spectra.  As they absorb the frequencies (research their respective absorption spectra through Wikipedia or Google) of the radiation (not necessarily light) that passes through them, the light will scatter with re-emission at different frequencies (their respective emission spectra), as if reflecting off of  an object.  They wavelengths are the important part, and not necessarily the coherency (as inherent in lasers) which tends to constructively interfere to produce "laser speckle."  The primary reason one might choose a laser is ability to key the energy on the specific frequencies of interest and to control the path of the light.  You would want mirrors on the ceiling and the floor to be perfectly aligned to allow the reflected beams to cover more area of the "laser wall" with multiple reflections from partial reflectors distributing the energy from a primary source through multiple small holes in the mirrors on the floor.  Alignment of the optics, and stability (environmental isolation) would be critical issues of the system.  Normal vibrations and movements of the geology and the house will interfere with the alignment unless properly isolated from it.
940858
The radio waves currently used for telecommunication or broadcasting are electromagnetic waves (non-ionizing radiation) which do not have enough energy to ionize atoms from materials. Although some of the electromagnetic waves, such as ionizing radiation including X-ray or gamma-ray, have high frequencies and strong energy that ionize atoms, they are very different from the radio waves we are dealing with; that is non-ionizing radiation.
1053320
As frequency increases the wavelength decreases and the equipment needed to transmit a certain distance doesn't need to be as strong. This allows the same powered transmitter to transmit a longer distance. This is why radio frequencies can travel a long distance but the output of a loudspeaker cannot.\n\nI think that was the answer you were looking for, since attenuation would be device dependant.
490442
We've been around radio waves for many years, even before you and your parents were born.  There is no harm to the human body.  If you installed a wireless LAN at your house, you will be OK.  With or without it, you will always be surrounded by radio waves.  No worries. :)
1140798
go to: radioisla1320.com\nclick to hear live
370212
Simple. Grab a stopwatch. Go outside. Yell, and measure the time for the echo to return to you.  Now, use the formula Mach*T/2 to find your distance from the wall.\n\nBeyond that, the Joint Spectrum Center & FCC probably have issues.
976253
For very long wavelengths (up to the visible spectrum), any thin layer will stop the radiation (consider a blindfold).  Even clothing will stop most.\n\nThe one used most commonly for radio frequency waves is called a Faraday Cage.  It is basically a metal screen box which has been grounded.\n\nUltraviolet rays can be stopped with a sun-screen.\n\nIf the wavelengths are very short (x-rays), then a lead shield is more suitable.  X-ray technicians also have aprons and throws which will stop most, if not all, x-rays.\n\nSome ultra-short wavelength EMF are almost impossible to stop.
108576
It has to do with horizontal and vertical lines of magnetic propogation, and it also deals with the way that EMI fields of energy will dissipate from an antanae when a volatage is applied through it.\n\nBasically you will use different shaped antenna to get better RF coverage to certain areas.
27336
In addition, you will have to raise the transceivers above the obstructions.  These signals are notorious for being "line of sight", and are easily obstructed.\n\nThe easiest way is to get a mast and mount it on the roof.  If that is not possible, look for a HAM radio antenna tower.  You can stack them as high as you need in order to get above the obstructions.\n\nIt does not take much to block these signals.  Even rain can prevent them from going through.  Ask anybody who uses DirecTV or Dish Network about that.
151737
some radioactive form of light can penetrate,e.g. X-rays
18465
It passes right through.   \n\nThe friction of the waves passing through is why food gets hot in the microwave.  Cell Phones and Wi-Fi do not have much power behind them is why don't cook but if you stand right in front of a microwave communication tower emitter you will be one roasted dude.  The guy that invented the microwave oven had discovered the application while working on radar arrays for the military and a candy bar in his shirt pocket had suddenly melted while he was standing near the emitter.\n\nThe dad of a friend of mine got mad one day and decided to throw a microwave into the street.  It smashed the door but still worked when we plugged it back in.  Even with the door open !  It felt pin-prickly and unpleasant if you put your hand in while it was running--  Don't try this at home !!
762445
More complex radar systems, like those used at airports, allow radio waves to be imaged on a computer screen. They send out a beam of radio waves (like a flashlight sends out light), collect the waves that reflect of off distant objects, and reconstruct the wave pattern into an image (like the eye does with light). The result is displayed for the operator to see.
693154
Only if they are at the same distance from the station and the same atmospheric conditions. The farther the receiver, the longer it takes for the signal to be received.
226364
Unless you live within line of sight of the transmitter, radio waves usually bounce off the Ionosphere (that's in the sky) to reach your house. The Ionosphere is ionized by charged particles from the sun. Changes in the level of ionization may affect the the strength of the signal which is reflected to your radio.\n\nSo, \nblame it on the sunshine, \ndon't blame it on the moonlight, \nblame it on the ionosphere,\nthat your radio won't boogie!
281802
It can only go through very thin films. Light is very high freq. X-rays are used to find small holes in welds since they go through small places well, but not metal. The fact that they conduct electricity means the magnetic part will induce a current, which creates another wave (reflection).  I have heard there is enough light passing through plywood, you can look through with an amplifier, starlight scope, night vision.