I saw this site linked from another forum.
My BS detector is flashing madly. Can anyone either verify or offer info that can contadict the claims that U.S. $20 bills have RFID tags in them (that can explode?).
Couldn’t it simply be that US currency has metal threading?
The security thread does not go through the face.
See here
Shrug. Well they say $1000 mainly in $20s. So that’s 50 bills for a height of 5 mm. Expand it to 10 mm to allow for crinkles etc. The burns don’t look like they all happen at the right eye, but they all happen in the centre of the bill where it’s darkest.
My WAG (Q.E.D. can smack me down when he shows up). The point of greatest absorption of microwave energy in a turntable style would be the centre. Given the heat absorbing/shedding properties of the dark ink the local temperatures managed to reach 232C scorching the paper. Anyone got a spare microwave they don’t need? We could cut up some blank paper with a green dot in eth middle and check.
Besides I thought RFIDs still hadn’t reached the point where the tiny size implies was economical. Cite = Scientific American 01/04
Or maybe it’s the ink. From The Standford Daily
Likely the metal sparked, scorching the paper.
From an Anonymous Coward (no relation) on Slashdot:
Sounds like a reasonable WAG to me…even though it lacks a certain black helicoptors motif. 
I’m Canadian. Technically those are our (UN) helicopters.
News flash: Paper put in ovens burns. Microwaves are no exceptions.
The only difference is that in a microwave the burning occurs from the middle out. Just like anything else you heat in a microwave. Concentrations of ink probably help too.
RFID tags sounds like a clever idea for tracing ransom money and the like. But on every single note issued?? I doubt the practicality of this and the current costs would make it prohibitive.
As was suggested on Slashdot, where this story came from, it’s far more likely that the guy’s wallet still had a stray tag still hidden in it as an anti-theft device.
US money contains metallic ink. The radio waves are going to induce eddy currents throughout the ink and make it hot. This is exactly the same principle that those microwave pizzas use to cook the crust so it doesn’t come out doughey. Those little grey pieces of cardboard that you stick the pizza on are also metallic. They don’t burn like the money did because the coating is much more uniform and the whole thing is designed to withstand the heat generated.
There’s also a metallic strip in money, but IIRC it’s on the side and not on the face where the burn marks are in the pics.
Dang hamsters. Let me try this again.
I did a bit of googling and found this site which talks about some of the techniques that might make this sort of thing feasable in the next decade or two:
http://www.aimglobal.org/technologies/rfid/resources/articles/dec03/PrintedTags.htm
Even if they did manage to print 5 cent tags onto every bill, I still have a hard time seeing how “big brother” can manage to track your cash as it moves throughout our entire complex economy. They might be able to track certain trends by getting enough samples, but tracking one individual’s spending habits isn’t going to be accomplished by this.
If you mean a microwave cooks “from the inside out” this is a misconception.
I decided to put my money where this guy’s theory is. I work at a bank so I figured that if my bill did turn extra crispy I’d be able to get a refund. So I did a little experiment.
I put a new style $20.00 bill in my new microwave, (with a glass of water, so my microwave didn’t freak out. I Microwaved it for a good 30 seconds, and nothing happened.
Thinking it might just be a fluke, I put the $20.00 in the microwave by itself for 10 seconds, and again nothing happened. So either I just didn’t fry it long enough to make sparks, or I didn’t have enough bills in there to cause a reaction, or this guys full of crap. You can probably guess which theory my money’s on.
Oh, and as an after thought I think I’ll throw in the fact that previous microwave experiments have shown that 10 seconds is usually more than enough time to get a violent reaction from something containing metal.
Like a foil lined butter wrapper for instance.
But, that being said, the flaws brought up by my last post made me rethink how well I conducted my little experiment. So I proceeded to do two more to better test my earlier observations.
- First I took a large stack of bills measuring ~2 inches high, composed of mostly singles, but also 5’s 10’s and two new 20’s, and microwaved them for 20 seconds.
Results: Nothing happened, but the bills were slightly warm.
- Immediately after that experiment, I took one of the new 20’s off of the top of the stack and placed it into the middle. I then microwaved them again for 35 seconds.
Results: The bills appeared unchanged, and the only noticeable change during cooking was that the stack of money appeared to “settle” and unwrinkled itself.
When I removed the pile from the microwave, I noticed white smoke or steam coming from the center of the bills. Also, the bills were hot enough to burn me.
Oddly, the ones most affected by the microwave were the older single dollar bills. The bigger and more recently issued bills were cooler than the rest. However, despite the large amounts of smoke (likely steam) being emitted from the pile of bills, there were no apparent burn marks on even the hottest of the bills, and definitely not on the colder new style 20’s.
As far as the security features, the coloring of the bills was unaffected; the red and blue threads were unaffected, as was the security strip down the side of the bills. The only thing that looked different was the color changing ink in the corner. For two of the colors it looked the same, but when the bill was held so that the copper color showed, the copper looked much shinier than usual. Whether this had anything to do with the microwaving, I can’t say, I suppose the bills could just be very clean, but that’s the only thing that appeared to stand out to me.
Well, that and the horrid smell, so I would caution against trying this one at home.
I would also like to volunteer my services and those of my microwave to the SDMB should you require our services again. Hope we helped. 
Maybe the guy didn’t use a regular microwave. It seems to only target the new style 20, maybe it was some type of “new twenties” style death ray? 