Stories
Slash Boxes
Comments

SoylentNews is people

SoylentNews is powered by your submissions, so send in your scoop. Only 17 submissions in the queue.
posted by martyb on Monday March 11 2019, @07:53PM   Printer-friendly
from the Grape-Balls-of-Fire dept.

Aaron Slepkov, a Trent University physics professor, has published a paper describing why grapes spark when heated in a microwave.

The team found that a microwave -- with a wavelength of 12 centimetres in air -- is the exact same size of a grape in water due to what's known as water's high index of refraction, Slepkov explained. That's when something interesting happens, he said.

Microwaves accumulate and become trapped inside the grape, he said, and those light microwaves pack themselves in the centre and the grape begins to heat up. When a second grape comes in, or the other half of a cut grape, the microwaves concentrate at the sides near each other creating an intense electrical field.

The electric field becomes so high, he said, that it begins stripping electrons off sodium and potassium molecules, creating ions.

"Once you have an ion of sodium or potassium, then all hell breaks loose and the rest of microwave oven is feeding that spark, ionizing the air and turning it into ball lightning," he said.

Professor Slepkov pointed out that there are potential applications in antena design for cellphones or wireless routers:

"We're hypothesizing maybe you can change antenna design because the grapes are acting as a concentrator for wireless radiation or cellphone radiation -- effecting how we design antennas to help act as a signal booster," he said.

I suppose such a product could be considered a grape concentrator.


Original Submission

This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
(1)
  • (Score: 5, Informative) by chromas on Monday March 11 2019, @07:53PM

    by chromas (34) Subscriber Badge on Monday March 11 2019, @07:53PM (#812887) Journal

    Link [youtube.com]

  • (Score: 4, Funny) by Anonymous Coward on Monday March 11 2019, @08:52PM (1 child)

    by Anonymous Coward on Monday March 11 2019, @08:52PM (#812909)

    This is why I read my news at SN!

  • (Score: 0) by Anonymous Coward on Monday March 11 2019, @10:21PM

    by Anonymous Coward on Monday March 11 2019, @10:21PM (#812935)

    Physicists do drugs, get munchies... heard it a thousand times.

  • (Score: 2) by SemperOSS on Monday March 11 2019, @10:23PM

    by SemperOSS (5072) on Monday March 11 2019, @10:23PM (#812937)

    Theme for the next book club session?


    --
    I don't need a signature to draw attention to myself.
    Maybe I should add a sarcasm warning now and again?
  • (Score: 2) by legont on Monday March 11 2019, @11:39PM (2 children)

    by legont (4179) on Monday March 11 2019, @11:39PM (#812977)

    If we are to use heavy water bags instead of grapes, can we get some neurons out? It's a shame only rich children can afford fusion reactors at home https://motherboard.vice.com/en_us/article/3kgjvn/jackson-oswalt-explains-why-he-built-a-nuclear-reactor-in-his-playroom [vice.com]

    --
    "Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
    • (Score: 3, Funny) by c0lo on Tuesday March 12 2019, @07:05AM (1 child)

      by c0lo (156) Subscriber Badge on Tuesday March 12 2019, @07:05AM (#813115) Journal

      If we are to use heavy water bags instead of grapes, can we get some neurons out?

      Not a hell of a chance.
      But tell you what... it you stick you finger deep enough while picking your nose, you may be able to get out some neurons.

      --
      https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
  • (Score: 0) by Anonymous Coward on Tuesday March 12 2019, @12:29AM (1 child)

    by Anonymous Coward on Tuesday March 12 2019, @12:29AM (#812999)

    If you are putting your grapes in the microwave then you're doing it wrong. They don't need to be cooked (or nuked or heated or whatever it is that happens in the magical hot pocket lair). You just put the grape in your mouth. No appliances required.

    • (Score: 2) by driverless on Tuesday March 12 2019, @02:28AM

      by driverless (4770) on Tuesday March 12 2019, @02:28AM (#813034)

      We're hypothesizing maybe you can change antenna design

      Meanwhile, those of us living in the non-hypothetical world just don't microwave grapes. Fully backwards-compatible with existing antenna designs and microwaves.

  • (Score: 2) by Snotnose on Tuesday March 12 2019, @12:59AM (3 children)

    by Snotnose (1623) on Tuesday March 12 2019, @12:59AM (#813008)

    Now we have to change the grapes in our cellphones every time we charge our battery. Good to know.

    --
    When the dust settled America realized it was saved by a porn star.
    • (Score: 2, Funny) by RandomFactor on Tuesday March 12 2019, @02:21AM (2 children)

      by RandomFactor (3682) Subscriber Badge on Tuesday March 12 2019, @02:21AM (#813029) Journal

      Yeah, if you needed a currant charge.

      --
      В «Правде» нет известий, в «Известиях» нет правды
      • (Score: 2, Funny) by Anonymous Coward on Tuesday March 12 2019, @05:14AM (1 child)

        by Anonymous Coward on Tuesday March 12 2019, @05:14AM (#813081)

        I see you are once again raisin the level of discourse around here.

        • (Score: 0) by Anonymous Coward on Tuesday March 12 2019, @01:23PM

          by Anonymous Coward on Tuesday March 12 2019, @01:23PM (#813225)

          You people really need to quit wining...

  • (Score: 2) by urza9814 on Tuesday March 12 2019, @12:11PM (6 children)

    by urza9814 (3954) on Tuesday March 12 2019, @12:11PM (#813198) Journal

    So, grapes are mostly water, and humans are mostly water. Seems like a brain is potentially a similar water content and therefore similar refraction of a grape.

    If we assume the size of the grape is 1cm, and the average human brain is 15cm long, then presumably you'd need a wavelength of 12*15=180cm to reproduce the same effect in a human head, which would be around 1.6GHz.

    Oddly, it seems a lot easier to find the length of a brain rather than the width, although I think for grapes it relies on width...but if we go with 10-11cm (which seems potentially reasonable based on my own head and tape measure) then the frequency comes to 2.4GHz.

    Don't get me wrong, I'm not trying to say the "wifi sensitivity" stuff is legitimate, pretty sure it's been pretty thoroughly debunked...but if one wanted to do some trolling.... :)

    • (Score: 1) by rst on Tuesday March 12 2019, @02:58PM (1 child)

      by rst (2175) on Tuesday March 12 2019, @02:58PM (#813286)

      A microwave oven uses 2.4 GHz, so either your math is wrong or the article's is.

      • (Score: 2) by urza9814 on Tuesday March 12 2019, @03:19PM

        by urza9814 (3954) on Tuesday March 12 2019, @03:19PM (#813307) Journal

        Ahh shit, you are correct, I did 180mm instead of cm...

        So what operates at 24GHz...?
        Looks like it's amateur radio and point-to-point network links. Not aware of any conspiracy theories around those. Damn... :(

    • (Score: 2) by Muad'Dave on Tuesday March 12 2019, @04:14PM (3 children)

      by Muad'Dave (1413) on Tuesday March 12 2019, @04:14PM (#813335)

      Your math is off by a factor of 10. If the ratio of grape to head is 15, then the resonant frequency would be 2.45 GHz / 15, or 163.3 MHz.

      • (Score: 2) by urza9814 on Tuesday March 12 2019, @04:51PM (2 children)

        by urza9814 (3954) on Tuesday March 12 2019, @04:51PM (#813350) Journal

        Jesus, I should not be trying to math that early...I even posted a correction in which I went the wrong damn direction. Thanks. Good thing my ham license expires this year, I probably don't deserve that anymore ;)

        So, 163 MHz...I see nothing of interest (particularly to conspiracy nuts) around that frequency...damn...

        • (Score: 2) by deimtee on Tuesday March 12 2019, @05:24PM (1 child)

          by deimtee (3272) on Tuesday March 12 2019, @05:24PM (#813369) Journal

          The article states that the RI (refractive index) is very frequency dependent. At microwave freqs, for some reason the RI goes up over 10 and the resonant wavelength approaches the size of a grape. It's not just a matter of scaling the sizes to headsize, at the new wavelength the RI will be different. You need to find the frequency that has a wavelength the size of the human head, while the wave is in the head.

          --
          If you cough while drinking cheap red wine it really cleans out your sinuses.
(1)