Microwave Definition and 349 Threads

I found this the other day and was wondering if it could work. If nothing else it is an interesting concept. http://www.keelynet.com/energy/microeng.htm"

I'm working on a bandpass filter at 3.2 GHz. I built a few prototypes interdigital, pipecap cavity, and even microstrip. Microstrip filter sort of works but it can't be tuned, so I abandoned it. The other types also work, bandwidth and insertion loss is ok but they all exhibit garbage...

If the EM waves emitted by a cell phone and a microwave oven have similar frequencies, what does it mean that the waves emitted by the oven contain more energy? I believe that a microwave oven generates about 500 watts, whereas a cell phone generates only about 2 watts. What exactly does that...

Not the waves, but the cooking device. I am curious how the radiation is generated, and why it stays inside the microwave (the outside doesn't get hot).

If I place a quart jar of water that has been tested positive for bacteria into a 1000w microwave, how long will it take to kill 100% of the bacteria. Thank you, Dell

I heard of several kinds of power plants, and then I came upon microwave power plants. I know what microwaves are, but how do they generate power? Would someone explain to me how or give me a link to somewhere?

So we did a series of microwave optics experiments in lab. We determined the wavelength of microwaves produced by a transmitter and we measured the interference and diffraction patterns due to various slits (double slit, single slit, circular aperture, etc). Well, for one of the apertures we...

If you happen to see microwaves... Scientists Take Step Toward Invisibility http://www.nytimes.com/2006/10/20/science/20cloak.html?hp&ex=1161316800&en=cd2cdec26f18ae3a&ei=5094&partner=homepage See also: http://www.ee.duke.edu/~drsmith/cloaking.html

Greetings, Earlier this afternoon I managed to ruin a perfectly good plastic container in a microwave oven by unwittingly deforming it. I curious as to why it happened. All I did was warm it (and the chilli inside it) for about a minute with the lid firmly secure. I've been told this was a...

I was wondering if any pro chemists on here have a decent amount of experience doing suzuki coupling reactions. Currently I am trying to couple alkyl boronic acids to a bromo pyridine in the microwave, but seem to be having a lot of trouble. The only thing that I am observing so far is removal...

Hi, This problem has me stumped and I keep thinking that I'm missing something simple. The question gives us a simple model for modelling a microwave. We consider a plane wave traveling through an object in the microwave (in the z direction), with no reflection. So, the general form should be...

What exactly is this and where did it come from? In detail if possible please

http://jnaudin.free.fr/html/oa_plasmoid.htm Is this possible, is it safe? What are some fun things to do in your microwave? What would happen if I put a golfball in?

Just looking for confirmation of a few thoughts and a couple of requests for information. Firstly, there are two significant processes when observing evanescent waves between two prisms, right? Firstly, the evanescent wave travels along the boundary of the reflecting material and regenerates...

As a fan of easy reading material on thorny topics, I thought some might find this interesting: http://www.arxiv.org/abs/astro-ph/0601307 Cosmic Microwave Background Mini-Review

Ok, since i can barely enjoy the godly food the local deli has prepared to me... I am going to rant. I hate microwaves with really massive foods like this slab of lasagna. The food never heats up evenly. They toss some instructions on the package going "Microwave for 3 minutes". My ass... I put...

I found this just a while ago... http://amasci.com/freenrg/magputt.txt The whole idea is to take a magnetron froma microwave oven and install it in a combustion engine. The problem is this guy says it is to be used as a steam turbine, not a combustion engine (and that it is the most...

One thing i was wondering is how efficient is a microwave? I kinda feel like its equivalent to using a firehose on a paper sack fire. So does anyone really know how efficient they are when it comes to heating up your food? And i mean like... efficiency... i mean how much energy do you need to...

My chemistry teacher recommends (for safety) putting a glass of water behind a microwave oven. She says this directs the microwaves (gives them somewhere to go) and helps to keep us from absorbing them and any harmful effects. Does it really do any good?

Do materials exist which can efficiently reflect microwaves, radio waves and other long wavelength electromagnetic waves?

Does a device exist which can generate microwaves using heat (e.g. hot air) as a power source?

This paper just came out this month http://www.arxiv.org/abs/astro-ph/0508047/ On the large-angle anomalies of the microwave sky C. J. Copi (1), D. Huterer (2), D. J. Schwarz (3), G. D. Starkman (1) ((1) Case Western Reserve University, (2) University of Chicago, (3) Universitat...

I'm not really sure where this question goes. I was wondering why metal behaves so violently when exposed to microwave radiation. For example if you put a metal object into a microwave, it sparks and if there are things attached such as plastic tops will explode off of what ever is in it. What...

Hey All ! i am basically a computer networks guy, exploring the telecom internals if i am so newbie please forgive me ! my question is that ! Is there any relation between the Wavelength and the distance covered by a MICOR WAVE when radiated through an anteena. Bascially i am...

Hello everyone. I thought I might be better off starting in this forum, but I wouldn't be surprised if this thread will be moved to one of the physics boards. 1. Reheating meat, activates bacteria, which is not healthy for us humans, correct? 2. While operational, everything inside the...

Not sure if this is the right forum for this question (maybe I need some microwave theorists instead?) , but: a friend of mine was telling me about an article she read about microwave food being unhealthy for you. Apparently, living off a diet of microwave for too long, even though you are...

These are probably the newbest of newb questions, possessing of a level of ignorance that moves right past funny into sad...however, being the curious type that I am, I'm going to tempt the cat's proverbial fate, and ask anyway. 1) My understanding is that microwave ovens work on the...

If I had a Microwave oven (minus the door), and I placed this at the back of a craft that was already in orbit, if I activated the Magntron, could this propel the craft? Stupid question I know, but if it can be a source of propulsion, what would be the maximum or minimum craft to microwave...

I'm currently sitting in a very cold room, it's cold because heating costs too much darn money (we haven't got central heating:(). Well, this got me thinking over cheap ways to heat a room. The idea of heating air with microwaves struck me being really cheap and effiecient. But it's so obvious...

I have trouble figuring out the following question. Please help. ------------------------------------------------------------------------ Suppose you want to melt a piece of ice and boil the resulting water by using a microwave oven. The radiation is incident upon one side of the ice which...

Just a comment on cups. Assuming that it was microwave safe, I recently put a new coffee cup in the nuke. After heating my coffee, I grabbed the cup and received a second degree burn - about half the size of a dime - with a small third degree burn [charring] in a portion of the first! Now that's...

I have been cooking these mini microwave pizzas lately and they come with a special round cardboard disk that you set the pizza on when you place it in the microwave. The top part of the cardboard disk has a silver-colored coating. I place this silver-side face up (per the directions), and put...

Hi. A mate of mine had a gemsquash (A type of pumpkin) blow up inside his microwave and now it won't work. I have heard that troubleshooting for microwaves is quite straightforward. Does anyone have advise on what to look for?

microwaves don"t pass thru the door of the microwave oven :confused: How come microwaves don"t pass thru the door of the microwave oven. Those small holes I believe have to do with this right? but how?

Greetings all, I've recently been wondering why I see sparks of light when I stick certain metal objects into a microwave. I figured that it has something to do with photons supplying energy to the electrons. When the electrons gain the energy they move to higher energy levels, but when they...

i read a article and i can't really understand all of it. I get some but then its beyond me. If someone could briefly summarise it so i can understand. Here is the link. http://www.aip.org/enews/physnews/2003/split/624-1.html

My textbook says that in microwave ovens, the frequency of the microwaves produced matches the natural frequebcy of water. Therefore, food containing water will heat up. But sites I have found on the net say a variety of other things. Such as 'It's a common misconception that the microwaves in a...

I once asked a JPL engineer if radio energy could affect a magnetic field, his answer was just plain no. But I have a problem with microwave RF affecting bipolar molecules. I mean microwaves cause these molecules to vibrate and they do so because the RF affects the electric and magnetic fields...

Did any experience that before? I was in the lab, luckily, microwaving 100 ml of water in an *open, no lid* 500 ml erlenmeyer flask. All of a sudden there was this big *boom* in the microwave like an explosion, when I open it.. water is dripping from the sides and about 25 ml were missing I...

microwave wattage... How is output wattage determined for wireless devices? For example, microwave ovens emit sound waves at similar fequency to wireless devices, yet they cook food. I know my cell phone is at 2.5 ghz, but the wattage output is so low that it supposedly does not affect me. My...

Do anyone know why the group velocity of microwaves inside a rectangular waveguide goes up when frequency goes up? To me it seems like a higher frequency means a smaller wavelength, and thus a more ZIG ZAG patterns off the walls (to meet the boundary conditions). If the wave is zig zagging...

Why hasn’t the background microwave radiation from the early universe all burnt out by now? (Penzias, Wilson, Dicke, Peebles, and George Gamow’s discovery of background radiation is what I am referring to.) I’ve heard a couple reasons on what caused the radiation… One about antimatter and...

Is is true that heating food/fluids using microwaves leads to a higher risk of cancer?

I need help with the following questions. 1.A microwave oven produces electromagnetic radiation at lambda = 12.3cm and produces a power of 764W. Calculate the number of microwave photons produced by the microwave oven each second. 2.Compton used photons of wavelength 71.3 pm. (a)...

I want to build a low-amplitude microwave generator. Nothing as strong as in real microwave ovens. I believe I have most of the theoretical knowledge needed, and I am willing to spend up to 200$ on materials. Any idea where to start? Anyone tried this himself once? Thanks :)

Hi My neighbour has microwave sensors, and the microwave beam comes through the walls of my house. this sort of thing i think- http://www.chubb.co.uk/pdfs/IPS_PDF/IPS212.pdf I want to know how I can stop the microwaves. I thought wallpapering the walls with aluminium foil. If the...

I have revisited Naudin site. He is still around with the lifters, and it seems nobody has been killed by X-ray radiation. Good. Besides this, he now is suggesting a couple of funny ways to destroy your mom microwave, by generating a small plasmoid inside. This guy is probably the nightmare of...

Just a quick question on microwave ovens if anyone knows it... If an oven is said to be 1000 Watts, does that mean it would use 1000 watts of electricity from the socket, or is that the rate at which food inside absorbs energy? If its the first, what would the rate of energy be that the...

The Microwave Bomb Well, it's pretty hard to miss the fact that there is a war going on right now... One rumor going around is that the US will test a new type of munition, a so-called microwave bomb. Does anyone have an idea how this device works?