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Gamma radiation is produced in large tropical thunderstorms

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Re: Gamma radiation is produced in large tropical thunderstorms

#131

This somehow reminds me of the fact that you can produce (surprisingly high-quality) x-rays by unrolling scotch tape in a vacuum chamber[0][1]. I wonder if it turns out to be related in any way. Thunderstorms aren't a vacuum of course, but I dunno, maybe all that frozen hail being thrown around can bumping into each other still involves a similar underlying mechanism somewhere. [0] https://www.nature.com/articles/nat…

You don't even need a vacuum to get a decent amount of xrays. Two drills going through a roll of scotch, reel to reel, will generate enough x-rays to take a rudimentary xray image of a hand.

Re: Gamma radiation is produced in large tropical thunderstorms

#132
post #119

Earlier quoted context omitted.

What is holding the tape to itself, what is making it sticky, if not chemistry?

For pressure-sensitive-adhesive tape (cellophane tape) it's mainly fuzzy static cling--wetting and van Der Waal's forces [1]. Wetting is when two substances (even solids) intermingle at their interface. van Der Waal's force is when a negatively-charged area of one molecule lines up the a postively-charged area of another. [1] https://science.howstuffworks.com/innovation/everyday-innova...

I see, so you're saying static cling "at a distance" is different to the interaction of positive and negative charges in a chemical reaction?

Re: Gamma radiation is produced in large tropical thunderstorms

#133
post #2

Positively charged particles end up at the top of the storm while negatively charged particles drop to the bottom, creating an enormous electric field that can be as strong as 100 million AA batteries stacked end-to-end. Or put another way, 150 MV. What's with this media obsession with using obscure non-SI units?

I mean, you can screw it up using SI units too! Eg https://x.com/HaydenDonnell/status/1503916925713547264

> A strapping newborn baby boy is understood to have set a New Zealand record, weighing in at a whopping 6.85kg (15lb 1oz) - the equivalent of nearly seven 1kg blocks of cheese.

I mean, the kilogram is an SI unit, but uh, I do not know if clarity has been added here.

Re: Gamma radiation is produced in large tropical thunderstorms

#134
post #132

Earlier quoted context omitted.

For pressure-sensitive-adhesive tape (cellophane tape) it's mainly fuzzy static cling--wetting and van Der Waal's forces [1]. Wetting is when two substances (even solids) intermingle at their interface. van Der Waal's force is when a negatively-charged area of one molecule lines up the a postively-charged area of another. [1] https://science.howstuffworks.com/innovation/everyday-innova...

I see, so you're saying static cling "at a distance" is different to the interaction of positive and negative charges in a chemical reaction?

IANAChemist, but to extend the cheesy analogies chemical bonds are like joint custody in a divorce; two atoms share one or more electrons. If it's split more or less evenly then it's called a covalent bond. If it's stacked in one atom's favor then it's called ionic. If it's kind of in a gray area in the middle then its called a polar covalent bond. [1]

Adhesion, even due to electrostatic or van Der Waal's forces, doesn't cause an electron to be shared [2].

To switch up the analogy (again, IANAC): as I understand it chemical bonds are like a couples thing; if you invite one you have to invite the other, and if you are interested in replacing a chemical bond with one of the atoms you need to first tear the couple apart. That's because chemical bonds share an electron; to share a particular electron with a new atom you need to stop sharing with the first one. (Sort of. I believe it's a lot more complicated than that, with group marriages and such.)

Adhesion is more like a friendship thing. You might hang out together, but there's no intimiate involvement. The electronic bonds are still available, so each each substance can do its normal chemical reaction thing with other atoms.

[1] https://en.wikipedia.org/wiki/Ionic_bonding

[2] Despite my previous cheesy analogy, electrostatic adhesion is the real static-cling force, not van Der Waal's. (But electrostatic adhesion isn't what makes sticky tape sticky, van Der Waals is.) The former is between entire molecules or groups of molecules, one group having a total positive charge compared to the other. van Der Waal's is pin-point attraction between local differences in molecular charge distribution, and each molecule in total might be electrically neutral. For example, a neutral water molecule has two highly-positive areas near the Hydrogen atoms and a highly-negative region away from them.

Re: Gamma radiation is produced in large tropical thunderstorms

#135

This somehow reminds me of the fact that you can produce (surprisingly high-quality) x-rays by unrolling scotch tape in a vacuum chamber[0][1]. I wonder if it turns out to be related in any way. Thunderstorms aren't a vacuum of course, but I dunno, maybe all that frozen hail being thrown around can bumping into each other still involves a similar underlying mechanism somewhere. [0] https://www.nature.com/articles/nat…

What about guitar pedal velcro tape?

[0] "Correlation between nanosecond X-ray flashes and stick–slip friction in peeling tape" (2008) https://www.nature.com/articles/nature07378

> Triboluminescence is a phenomenon in which light is generated when a material is mechanically pulled apart, ripped, scratched, crushed, or rubbed (see tribology). [...] Triboluminescence is often a synonym for fractoluminescence (a term mainly used when referring only to light emitted from fractured crystals). Triboluminescence differs from piezoluminescence in that a piezoluminescent material emits light when deformed, as opposed to broken. These are examples of mechanoluminescence, which is luminescence resulting from any mechanical action on a solid. [...] See also:

> - Earthquake light: https://en.wikipedia.org/wiki/Earthquake_light

- re: gold from earthquake-induced piezoelectricity in quartz: https://news.ycombinator.com/item?id=41442489

- re: sustainable alternatives to quartz countertops: https://news.ycombinator.com/item?id=36857929 :

> [...] make recycled paper outdoor waterproof vert ramps, countertops, siding, and flooring; but not yet roofing FWIU?

> - Sonoluminesence: https://en.wikipedia.org/wiki/Sonoluminescence

Re: Gamma radiation is produced in large tropical thunderstorms

#136

If you dropped a thing through a storm to the water, would it charge the thing, from gamma radiation? TIL carbon nano yarn absorbs electricity, probably from storm clouds too. What are the volt and charge observations for lightning from large tropical thunderstorms? (And why is it dangerous to attract arc discharge toward a local attractor? And what sort of supercapacitors and anodes can handle charge from a lightnin…

On lightning and safety and electrostatics: "Answer to Is there a device that attracts lightning when storms are near? How can I make a lightning rod to do experiments with lightning?" (202_ yrs ago) https://www.quora.com/Is-there-a-device-that-attracts-lightn... :

Electrostatics: https://en.wikipedia.org/wiki/Electrostatics

The Photoelectric effect that supports the Particle-Wave duality > History: https://en.wikipedia.org/wiki/Photoelectric_effect :

> Einstein theorized that the energy in each quantum of light was equal to the frequency of light multiplied by a constant, later called the Planck constant. A photon above a threshold frequency has the required energy to eject a single electron, creating the observed effect. This was a step in the development of quantum mechanics. In 1914, Robert A. Millikan's highly accurate measurements of the Planck constant from the photoelectric effect supported Einstein's model, even though a corpuscular theory of light was for Millikan, at the time, "quite unthinkable". [47] Einstein was awarded the 1921 Nobel Prize in Physics for "his discovery of the law of the photoelectric effect", [48] and Millikan was awarded the Nobel Prize in 1923 for "his work on the elementary charge of electricity and on the photoelectric effect".[49]

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