4 Unholy Powers Secretly Wielded by Your Microwave

4 Turning Grapes Into Plasma

Let’s say you place two grapes into a microwave oven. To pull off this trick, it’s traditional to slice the grapes, but this isn’t necessary. The grapes touch each other, and there is nothing else in the oven. Turn the power on. Suddenly, flames appear, which isn’t something you remember being warned about when heating normal food. 

That isn’t actually fire. It’s plasma, the fourth state of matter, the result of electrons getting ripped out of atoms. Unnamed people stumbled upon this discovery decades ago, and generations showed it off as a party trick without ever understanding what was happening. 

Scientists finally hammered out an explanation in 2018. It’s a little too complicated to detail here, but in short: When an object contains a lot of water, microwaves create hotspots called morphology-dependent resonances. When two such objects are close together and touch at a tiny spot, which is largely only possible when the objects are somewhat spherical, these hotspots move toward each other and create an explosive electric field. This leads to arcing, which is the creation of plasma in the air. 

Oh, and when we described you doing this before, that was just a hypothetical. We don’t recommend actually trying it, as it may destroy your microwave, burn your house down or possibly kill your entire family. 

3 Electrocuting You When Unplugged

For another highly inadvisable thing you can try with your microwave, let’s talk about taking the device apart by hand. 

Obviously, you aren’t going to do this while the oven is in operation and heating food. You’re not an idiot. Equally obviously, you’re not going to do this with the appliance still plugged into the mains supply, because you’d surely end up touching a live wire and electrocuting yourself. But even with those precautions, tinkering around with the insides can still shock you.

A microwave oven takes in alternating current and converts that to direct current. But unlike the sort of adapters that step down voltage to a comfy 12 volts, this one steps it up to 4,000 volts because that’s what’s needed to drive the magnetron. The capacitor inside the microwave retains a charge even once you’ve pulled the plug, and that’s the part that might just end up sending a jolt right into your chest.

Engineers offer tips on how to safely discharge the capacitor so you can bang away at the insides with impunity. But given the occasional story of people who die from electrocution when repairing microwaves, we’re just going to say to leave yours screwed tightly shut unless you’re a professional. 

2 Heating Metal Just Fine

In most arenas, heating metal isn’t a terribly impressive trick at all. Sunlight heats metal, as does hot air. But you’ve been told all your life that you should never try heating metal in the microwave. If you stick a fork in there by mistake, something terrible will happen. Though you’re not sure exactly what, it’ll probably be something like when you heat two grapes.

But what’s this then:

That’s metal, and it’s supposed to be placed at the bottom of a microwavable pizza. Plus, now that we think about it, the entire interior of the oven is made of metal. Clearly, then, not all metal is a hazard in there.

Metal, as you’re correctly picturing, reacts differently to microwaves than food does. It reflects waves, which is why the inner walls of the oven are metal. When metal is very thin, however, the metal does heat up, which can be useful for transferring heat to that pizza. 

Microwaves can also send electrons flying to spiky bits of the metal, which can indeed create dangerous plasma in the air. But that generally doesn’t happen to metal that’s smooth. Perfectly flat foil will probably be fine, while crumpled foil is dangerous. A perfectly smooth metal bowl may be fine, while a fork may be dangerous — but certain grades of stainless steel are particularly safe, so you might not be able to get a fork arcing plasma into the air even if you try. Incidentally, microwave ovens have improved a bit in design in the past half century and are better prepared for all kinds of threats. 

We’re not saying you should go out of your way to start popping metal in there. But if you do buy a metal bowl and see it’s stamped microwave-safe, believe it. You may be confused at first, since you’ve always heard metal has no place in the microwave, but you can trust this piece of cookware as much as anything else marked microwave-safe. This isn’t a conspiracy to kill you. 

1 Reanimating the Dead

So, we’ve talked about how a microwave may kill you and how a microwave may not kill you. And if you do die, bad news: That’s game over. There’s no way to come back from that. The science of cryonics seeks to freeze dead bodies long-term and then revive them, but we have never succeeded at bringing humans back this way.

We have, however, succeeded at bringing back smaller animals. Cryonics was making its biggest strides back in the 1950s, when scientists tried the process on increasingly large rodents, and it only stopped when they realized it becomes impossible on animals that are too large. They got as far as reviving a fully frozen hamster. 

To defrost this hamster evenly, a British scientist named James Lovelock came up with the idea of using electromagnetic waves of a particular frequency, and he built a device to do this. He brought back a frozen hamster that was by any normal measure dead, and he did it using a microwave oven. He did not film the process, so we’re going to show it reenacted in the 1993 video game Day of the Tentacle:

It’s pretty crazy that a microwave could be used for this. But you know what’s crazier? The fact that this was the original purpose for which the microwave oven was invented.

You might have heard the famous story that microwave cooking was invented when a scientist happened to walk near a radio antenna with a chocolate bar in his pocket and discovered that the waves melted the chocolate. He went on to build a magnetron to produce microwaves to cook food, and the first food he tried was popcorn. This story is true. However, Lovelock created his microwave oven independently from that American scientist, starting from scratch to produce microwaves to reanimate frozen corpses.

And Lovelock’s microwave oven has the better claim at being the predecessor to today’s devices. The microwave oven created by American engineer Percy Spencer stood six feet tall and weighed half a ton. That was also what the devices were like when the first commercial versions hit the market:

Lovelock’s device, on the other hand, was a countertop box that looked much more like the ones we have today. He built it that size because he wasn’t thinking about industrial kitchens maximizing efficiency. He was thinking about what box would be a reasonable size for resurrecting rodents.

So, if you ever wonder why your baking oven is a huge cubby that a small child can crawl into while your microwave oven is only big enough for a single plate, don’t say it’s because one is for large-scale cooking and the other is for dinner-for-one. Say it’s because one is based on a roaring fireplace while the other is based on a hamster cage.

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