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A Stable Plasma Ring Has Been Created In Open Air For the First Time Ever (futurism.com)
New submitter mrcoder83 shares a report from Futurism: Engineers from the California Institute of Technology (Caltech) have been able to create a stable plasma ring without a container. According to the Caltech press release, it's "essentially capturing lightning in a bottle, but without the bottle." This remarkable feat was achieved using only a stream of water and a crystal plate, made from either quartz and lithium niobate. The union of these tools induced a type of contact electrification known as the triboelectric effect. The researchers blasted the crystal plate with an 85-micron-diameter jet of water (narrower than a human hair) from a specially designed nozzle. The water hit the crystal plate with a pressure of 632.7 kilograms of force per centimeter (9,000 pounds per square inch), generating an impact velocity of around 305 meters per second (1,000 feet per second) -- as fast as a bullet from a handgun. Plasma was formed as a result of the creation of an electric charge when the water hit the crystal surface. The flow of electrons from the point of contact ionizes the molecules and atoms in the gas area surrounding the water's surface, forming a donut-shaped glowing plasma that's dozens of microns in diameter. Caltech posted a video of the plasma ring on their YouTube channel.
"generating an impact velocity of around 305 meters per second (1,000 feet per second)"
Ok, the actual science was done measuring meters per second, the press release rounds it to a nice round number of 1000f/s for American audience, and then that rounded number is converted to a quite exact figure of 305m/s.
In the actual paper, the experiment was done with a wide range of velocities. Over 200 m/s was required velocity to generate the effect.
I'm an electrical engineer.
First of all I want to clarify that they mean static noise, not static charge. The first one is the "waterfally" sound you get from your regular AM/FM radio not tuned into a channel. The second one is what happen when you rub a balloon against a cat.
There is no physical difference between a wire and an antenna. If you want to design an antenna you can just cut a wire to an appropriate length (Or any length, it doesn't have to be a good antenna to work as one.)
Every trace on a PCB, like the ones between the CPU and the the memory, or the ones to the speaker works exactly like antennas.
You usually don't care about this property of wires and traces since the impact of the radio waves is so insignificant.
The signals you work with are much stronger than the impact the radio waves have.
So what happened here is probably that there is a DA converter in the phone that requires some filtering to not sound like crap and that filter is placed too far away from the amplifier for the speaker. The trace between the filter and the driver picked up radio noise from the plasma.
The DA is probably integrated into the CPU so they couldn't move it closer to the amplifier and if they moved the filter closer to the amplifier they would emit more radio signals themselves.
You typically won't encounter open air plasmas in your daily life so it isn't really a big problem.
There is a lot more to talk about here, but I hope this clarifies what the two of them has to do with each other sufficiently for now.
The water hit the crystal plate with a pressure of 632.7 kilograms of force per centimeter (9,000 pounds per square inch)
Everyone seems to have missed the really important detail.
The strange quantum effect which changes the dimensionality of the effect from 2D to 1D depending on the units used to make the measurement.