Who would have thought that you could microwave a cut grape for just a few seconds, and produce a glowing plasma in your microwave. Have a look at this instructional video (NOTE: I am not telling you to try this at home, but if you do, report back.)
The explanation, from Now I Know:
The two sides of the grape act as focal points for the microwaves (the waves themselves, not the appliance). The grape haves are connected only by the thin piece of skin left uncut by the knife. As the microwaves move across the grape, from one hemisphere to the other, this tiny remainder of grape skin quickly dries out and burns up, causing a spark.
And one spark is all you need. It ionizes the air around the grape, creating ion-rich gas also known as a plasma – with solids, liquids, and gases, the fourth form of matter. The light show you’re seeing is the plasma, much like that as seen in a plasma lamp, albeit more violent and because it is in your microwave, dangerous.
Why is the plasma in the video above so large? The team at The Naked Scientists explains further: “This plasma conducts electricity and can absorb microwaves. Sometimes the plasma gets big enough to absorb enough microwaves to keep growing[.]” The Naked Scientists also warn that the experiment “can cause minor burns on the top of your microwave.”
The glass contains the air around the grape even more so than the microwave oven, thereby concentrating the plasma, and allowing for the light show seen in the video (as well as protecting the roof of the microwave).
h/t: Diane G.
EXCELLENT!!!
Neat – I’ll be showing this trick to my nieces and nephews this holiday (using my sister’s microwave of course).
Me too!
One of my first forays into the Internet – in around 1994, via Compuserve – resulted in a text file full of “microwave tricks”, including this one. Since that was at least a half-dozen years before I got a microwave, I never actually tried any of the experiments, but they sounded entertaining and informative.
Compuserve. 1994 or thereabouts.
That brings back memories. Terrible, oppressing memories of the time when attempting to download a 5mb file was an exercise in masochism, so slow was the connexion, and so frequent the deconnections… and you had to being at zero again after each.
And each time, the 56k modem would mock you, taunt you, curse you in a harsh, rasping voice darker than the Black Speech of Mordor.
Even now, I shudder to think of it.
Surely the word “Compu*erve” should be treated as a “trigger”.
Well, at least it wasn’t a 2400 modem. 🙂
… which was what I started with.
2400? I would have killed to swap my 300 baud acoustic cradle for 2400!!!
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… back in my days… carrier pigeons… uphill both ways…. etc…
We did have a 300 acoustic coupler. but since the school’s computing course had no budget (literally : budget : £0.00 per annum), and no phone line we had to wheel the terminal to the school office where the telephone was (including up two sets of 5 stairs each – a problem for the physics and engineering departments) in order to dial into the local college’s mainframe. (Which cost IIRC £0.50/hour, after 6pm. But since the courses were all after-hours … that was less of a problem compared to moving the machine.)
It was much more manageable to write your code onto the coding forms, then a week later get the results of the run back as paper tape (programme tape and results tape) ; the coding and running was done in the normal process of the operators at the college and wasn’t charged.
Contrary to what some people think, it really is easier these days.
You win, grandpa 😛 I have never even seen an acoustic coupler in the wild,… and I’m perfectly happy with that.
> Contrary to what some people think, it really is easier these days.
Some people actually think that ?
I’ve never met anyone saying that perforated cards and FORTRAN were the bee’s knees. I would be very curious to meet some, if only out of anthropological curiosity.
I’d think technology and computing old-timers would be the least susceptible group to the “better in my days” fallacy. 1° undeniable, rapid, constant, spectacular improvements make it a very difficult position to take, and 2° if you started paying attention to technology in or before the 80s, it probably was as a deliberate act of curiosity; it was still natural and easy to ignore, dismiss, and live without the newfangled thingies if you weren’t curious. Curious people tend to recognise and value progress.
And now I go back to ignoring, dismissing, and living without those newfangled twitter, facebook, cell phones with integrated coffee makers etcetera, all thingies and gizmos that serve no purpose I can discern. Bah humbug!
I think the “better in the old days” crowd speak unclearly due to the close lingual-buccal interference fit. At least, the computing ones do.
OTOH, we didn’t have to deal with maintaining Ad-Block filters “back in the day”.
I saw the first (to me) complaint about an inadequately firewalled coffee pot while catching up on a webcomic yesterday. (For context, the “Dr Bowman” later describes himself as “the defective chimp bioweapon who designed the robot brains that are terraforming this planet.” Which should give you a large chunk of 2500 3-panel strips of back story.)
(hum, can’t reply to post but only to its parent; does WordPress hate recursion?)
> I think the “better in the old days” crowd
> speak unclearly due to the close
> lingual-buccal interference fit.
The LISPers ? Bah, they should look at the begotten wonders that are OCaml and Haskell etc and be very happy indeed for such a legacy.
I don’t know how the parenthesis-infested dialects are faring nowadays, but I doubt that they are moribund.
> OTOH, we didn’t have to deal with
> maintaining Ad-Block filters “back in the day”.
Autoplay Video+audio ads are especially hateful. I have even seen some playing at the same time as the main video. Curse you, Flash and HTML5!
> Dr Bowman … defective chimp bioweapon
Natural 20 on your Spoiler Attack, roll 9d6 for damage. Then double it!
I actually stopped reading Freefall for over a year, the idea being to (eventually) have a decent-sized chunk to catch up with… and I even dared hope that the chunk would include tangible and *surprising* revelations about the mysterious Dr. Bowman…
I remember limping through LISP with paper tape. Those were Da Daze;-)
WP gets upset of you try more than about 5 levels deep through the web page. But if you use the “notifications” section, you always get a “reply button, though you’re shorn of context.
Nope. “Lingual” = about tongues ; “buccal” about cheeks. No rimming involved.
“Great minds”, or “fools rarely”?
I’d stand up for a good wag, but I don’t have the anatomy.
No notifications, just a bookmark — I’ve got quite enough mail to my taste already. I’ll make do with bounded nesting…
>>The LISPers ?
>Nope. “Lingual” = about tongues
No argument there.
>“buccal” about cheeks.
> No rimming involved.
English is not my mother tongue (there is a theme, here), so it took me 5 rather bewildered minutes (after Googling “rimming” to check it was what I thought it was) to even understand the thought process under that association of ideas. [buccal only means “of the mouth” in French. And gave us “bouche” for “mouth”; further we have “joues” and “fesses” and never the twain shall meet, so that it didn’t occur to me to confuse cheek and cheek until I made a deliberate effort. Sapir-Whorf hypothesis and all that jazz. With an other reference to anatomy in the post, we came quite near some hilarious misunderstanding.]
Anyway, LISPers did fit quite well, what with the death of Lisp Machines and all. (and buccal can *also* mean of the mouth in English).
> “Great minds”, or “fools rarely”?
Let us be reminded that we are in the thread that began by comparisons of the size and merits of our respective first modems. That severely restricts the search space for pop-culture items that are likely to pop up, let’s admit it!
Also, the “fools rarely” clause of that saying makes no sense to me. I expect well-functioning minds to converge — from the same initial conditions — because they pay attention to reality and rigor and will actively seek to resolve disagreements among them by empiricism and math (cf. Aumann’s agreement theorem). But fools are not so constrained — pretty much by definition — and so given some time, I expect 1000 fools to come up with (at least) 1000 different conclusions, with no way to eliminate any. Fools *do* differ. That’s a pretty important point wrt. science and religions, I think.
Oh, sorry. Linguistics :
“lingual-buccal juxtaposition” : “tongue in cheek” – an ironic or deliberately comic position taken more for effect than substance of argument.
A common English (British) rhetorical question when in close agreement is “Are we great minds thinking alike, or fools who rarely differ?” (various minor variations).
> “lingual-buccal juxtaposition” : “tongue in cheek” an ironic or deliberately comic position taken more for effect than substance of argument.
I know what “tongue in cheek” means, that was never the problem.
I was explaining why, of the two valid interpretations of the pithy “lingual-buccal juxtaposition” (in English): “tongue in cheek” and “tongue in mouth”, I chose the second (which would be the only one in French), and that it fit in context: LISP is a programming language, and a lisp is a speech impediment involving “errors in tongue placement within the mouth”. A “lingual-buccal juxtaposition error”. It fit.
I assume “lingual-buccal juxtaposition” is your own humorous coinage, and not an accepted, tongue in cheek way of saying “tongue in cheek”, for, dare I say, extra cheek? [And yet another meaning of cheek that does not translate in French…]
> “Are we great minds thinking alike, or fools who rarely differ?” (various minor variations).
The variation I know is not in the form of a question, but of an assertion: “Great minds think alike, and fools seldom differ.”
In the previous post I was questioning the wisdom of the second part of that saying — I think it’s exactly the wrong thing to say.
Of course if you were thinking of the question form, my remark would not have made sense for you when you read it.
[And I wrote a looooong post again; sorry, I have the urge to clarify things when I perceive mis-communications… which leads to more opportunities for further fun mis-communications, which….]
I did get the LISP jokes too. Never programmed (it), and I’m not sure if that’s a good thing (or a bad thing(.))
> I did get the LISP jokes too. Never programmed (it), and I’m not sure if that’s a good thing (or a bad thing(.))
If you’ve never done any functional programming, I’d say “bad”, although that’s not the language I’d recommend for that: http://ocaml.org/ .
The difference is that the LISP family “implements” lambda calculus, and the ML (OCaml, Haskell,…) family “implements” *typed* lambda calculus, and allows itself a more compact syntax. The type-system is *very* sophisticated; it’s basically a built-in theorem prover: if your program is incorrect, it won’t compile. eg if your website *can* produce invalid HTML5 for *some* input, it does not compile. (of course there are limits to what the type-system can do; cf. computational complexity).
Surgeon’s Warning: learning OCaml may completely and utterly spoil your programming experience in C,++, C#, Java, etc. It did for me; Scheme (LISP), which I learned years before, did not.
My programming practice is “this is the programming director’s idea of what he wants in our product. Make it sing and dance. DO NOT UNDER ANY CIRCUMSTANCES document ANYTHING! If you do that, the support department loses calls and this may threaten your friend’s employment.
when the new version comes out (and it is brought by clients I work for), I’ll need to learn Python. (A dialect called Iron Python, I’m told.) [SHRUG] shouldn’t take more than a few days – though learning our class library will probably take a few weeks. Then I start finding the bugs.
That said, this week I’m using the 2011 version and next month I’ll be on the 2009 version. When I get to see the 2015 version I don’t know. Or much care.
> My programming practice is
Oh dear. This sounds like something out of TheDailyWTF. I hope companies with that soul-crushing philosophy are the exception rather than the rule, and that you have plausible plans to go somewhere less revolting post-haste. Not sure how naïve that hope is; you certainly don’t *sound* like you anticipate things will be better soon.
Though I shouldn’t be surprised. Previous experiences teaching third-year CS students showed that “clean, clear, and reliable code is good” is not a self-evident, axiomatic statement for a depressing proportion of people who are getting CS degrees. I can totally imagine them adopting a “don’t document anything” policy, once released in the wild, with no mental alarm setting off.
Well anyway, Christmas cheer and all that…
“clean, clear, reliable code”…and Elegant! Occam’s Razor, less is more…(but, of course, with documentation)
Programming is a minor part of my job – a very minor part. And for the next few years I’m effectively on secondment to run my own little training school bobbing around the world. So the head office can away and boil their heids. I’ve seen that department come into existence, and I’ll see it die. “This too, shall pass.” As some philosopher type gadjie once said.
For those that are impatient like I am, you don’t see anything cool until 1:40.
Surely we can turn this into a weapon somehow?
An update to grapeshot?
I actually LOLed. (Is it OK to use it as a verb? – must check da Roolz.)
I know of two applications
[1] So-called Active Denial Systems [crowd control], but luckily it’s proved ineffective due to a whole slew of problems especially the difficulty of building a compact, portable power source, funnelling the effect, medical/political concerns
One type used a particular microwave frequency that sets up sound waves in the recipients brain & another was designed to penetrate a few mm of skin to cause pain. I believe there’s nothing out there in use.
[2] One shot systems where the power source is an explosive – destroys the microwave generator during operation. Used to knock out electronics via microwave pulse & AFAIK it kind of works in the form of a guided missile that explodes near the target & buggers up any unshielded electronics nearby.
I’m sure what I know is way behind what’s really happening but I imagine microwaves will always be used mostly for electronic counter measures rather than for burning targets.
A weapon against relatives you don’t like. Just say you want to borrow the microwave for a sec to make some hot grape cider…wabam.
He lost me at ‘I think the glass might shatter’ and ‘fumes may not be good.’ I will stick to the videos.
Yep.
I also have a hypothesis about the approximate age and gender of viewers most likely to try to replicate this. 😉
(Though I could see me as a kid trying it…good thing we didn’t have microwave ovens back then…)
Old ladies, right?
Well…you’ve narrowed it to species…
😀
Let me see… Age range of 55-60… Yes!
And you have…the right order of magnitude…
Email to Dad a couple of weeks ago :
Does WEIT know about the “fly-killer” explosive, nitrogen tri-iodide (so-called)? Oh yes, I’m sure I posted video here recently.
Would I do a thing like that? 💣 ☮
Sigh. Many happy memories, but not so much for the piano or the poor woman who was dusting it off the morning after our trap (very fortunately) failed to trigger while our intended victim was playing the thing. A duster was cremated, some keys went MIA but no real harm was done.
To mis-quote some pastor somewhere, if the Good Lord had intended us to not have purple mushroom clouds, then he would never have invented nitroglycerine. Or something like that.
Instead, I’m putting this in my ‘to try if I find an extra cheap used microwave’ file.
Prof. Coyne,
See this video for a dill pickle lamp:
https://www.youtube.com/watch?v=effgeTPjo2k
They don’t do this at Katz’s Deli, but they should.
It’s an old RF engineer’s party trick. I first heard of it while visiting some colleagues in New York. One colleague asked if I’d ever tried to split a grape in half and microwave it; I said “no, I never thought of using a grape as an antenna”. He didn’t want to demonstrate what would happen using the microwave in the office kitchen.
My youngest son is into this sort of science, and he and I have a history of getting into trouble — for science! Maybe I will show him this trick when his mom is not around.
I can see the reflection of the “scientist” in the glass and he is not naked.
Tip: if you’re going to post video of your microwave experiments, clean your microwave first!
I thought that too. 😀
I’ve also noticed that if you let your microwave get dirty enough, you may end up doing your own sort of microwave experiments.
Years ago we had a microwave with a button to Stop Time. We never pushed that button!
😀 😀
Thanks for that! Must have been tempting sometimes. Two quick taps, really fast…
We actually had people from a TV station in our lab at work who had received a viewer’s inquiry about chilis igniting in the microwave and wanted us to reproduce and explain the effect.
Our experiments showed that it not only works with chilis, but with virtually anything that has a hard enough peel (e.g. cucumbers, apples, pears, potatoes, bell peppers) and can therefore be cut into the shape described in the video. It also seems to work best with specimens that have the appropriate length (lambda/4) to function as microwave antenna, i.e. around 3 cm (1.2″).
We found it slightly more difficult to ignite moist things such as pears or sliced pickled chilis, maybe because the water prevented the bridge of peel in the center from drying up fast enough, or maybe because it simply increased the cross-section, thereby reducing its electrical resistance and in consequence the conversion of electrical power to heat.
We didn’t look into it in any more detail though, once the camera team had everything in the can – it was 11 p.m. already. However, we did have some fun with our relatives’ microwaves (not our own, of course, because it does stink after some time) 😉
Sub
There is a fifth phase of matter, the Bose Einstein Condensate which exists at a temperature near absolute zero.
What could be in the fumes, I wonder.
Well, since the guy was so foolish as to remove the glass turntable, the plasma had a chance to interact with the plastic floor of the microwave. So there’s probably gases being formed that you wouldn’t get from the grape alone.
His excuse for removing it was “you don’t want the grape going everywhere, you want it to stay in one spot,” but I don’t see why that should matter.
And there is a sixth form of matter, supercritical fluids, which have properties of both liquids and gases.
The fumes are probably the usual combustion products of organic substances, plus unreacted organic compounds vaporized intact from the grape, plus unusual compounds formed by the recombination of the gaseous ions. Which last ones may be acidic, since protons are undoubtedly be one of the ions formed. Those might be corrosive to the lungs when inhaled.
I like the fact that the ‘elements’ of prescientific antiquity (earth-water-air-fire) line up so exactly with solid-liquid-gas-plasma. Some genius got so close, but then called them ‘elements’ instead of ‘states’, and the next two millennia were wasted.