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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.
"Gharib’s team also noticed another peculiar phenomenon: the plasma ring emitted distinct radio frequencies, as evidenced by the high levels of static the engineers’ mobile phones picked up during the experiment. “That’s never been seen before. We think it’s because of the piezo properties of the materials that we used in our experiments,” Pereira explained."
Sounds to me like he's never heard of the plasma speaker.
https://en.wikipedia.org/wiki/...
"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.
What is curious is that they needed precisely 632.7 kilograms of force per centimeter [sic], to 4 significant figures. Even more remarkable is that this evaluates to almost exactly 9,000 pounds per square inch (8999.1 psi to be precise).