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Greentext @sh.itjust.works

🍹Early to RISA 🧉 @sh.itjust.works

11mo ago

Anon is a physicist

42 comments

Makes sense, why test it?
Excuse me, I have to get back to wiping my ass with the communal sponge-on-a-stick.
- Don't forget your lead cookware and lead infused wine!
  
  Makes everything sweeter. And the mental instability is less of a hindrance in times when people were regularly crucified.
  
  I prefer mercy in my wine. If you put enough you won't remember anything tasting better.
- but mom said it was my turn on the sponge-on-a-stick

Lucretius, writing in 50 BCE:
Whatever falls through water or thin air, the rate Of speed at which it falls must be related to its weight, Because the substance of water and the nature of thin air Do not resist all objects equally, but give way faster To heavier objects, overcome, while on the other hand Empty void cannot at any part or time withstand Any object, but it must continually heed Its nature and give way, so all things fall at equal speed, Even though of differing weights, through the still void.
De Rerum Natura book 2 lines 230-239
I was literally just writing about him nailing survival of the fittest too.
- He's still arguing that heavy objects would fall faster when dropped anywhere on Earth, though, specifically bringing up air resistance as the reason. His argument is that they would fall at the same rate in a vacuum.
  
  But that's true, isn't it? Putting aside volume and shape.

When air resistance is in the equation, weight can be a factor. But yes, it should’ve been checked way earlier, but it’s not surprising considering how he’s put on a pedestal.
- I read somewhere that Galileo really struggled convincing his patrons go finance such experiments. Science wasn't concerned with fundamental questions about how the world works until very recently
  
  That’s not necessarily true, they are definitely interested in how the world worked, they just used a very different set of assumptions and methodologies compared to what we use today.
- Not like we really had the ability to create a large enough vacuum to test it until, as far as human history goes, relatively recently

- This man managed to get a G out of the word "feathers."

this idea seems rather tame when you compare it to a bunch of other batshit crazy ideas people were having in ancient greece, like: each time an eel smashes into a rock, a tiny piece of eel breaks off, and then that tiny piece of eel turns into an adult eel and thats how eels are born.
- It's funny how they treated cancer:
  Treatment was based on the humour theory of four bodily fluids (black and yellow bile, blood, and phlegm). According to the patient's humour, treatment consisted of diet, blood-letting, and/or laxatives.
  https://en.wikipedia.org/wiki/History_of_cancer#Early_diagnosis
  
  Nowadays doctors are pretty humourless.
- Funilly enough, I think we still don't know how some eels mate, so maybe they were on to something

Heavy objects, on average, are denser at human scales. Dense objects tend to have an aerodynamic profile compared to sheets of leaves or cloth or sand. They tend to get blown away in the wind. Anything that would bind or compact those lightweight things together like resin or water tends to weigh a sizable percentage of the compound. There is a correlation between heavy and fall speed. It took accurate scales and 0 bar vacuums to prove it was the air doing it.
Try explaining how a helium balloon works without sounding like a wizard.
- They tend to get blown away in the wind
  True, but not because of "aerodynamic profiles". Create a sphere out of lead and one out of styrofoam and the lead one will land first. The real difference is air resistance. Probably the first piece of physics anyone learns is f=ma, and this tells us that with the same force (e.g. the same amount of air in the way when travelling at the same speed), a lighter mass will experience more acceleration (in the case of air resistance, less acceleration in the direction of fall, because of more acceleration in the upwards direction) than a heavier one.
  
  There's something to the aerodynamic profiles though. Less surface area results in less force being applied. So a flat sheet of paper falls slower than that same sheet crumpled up. The things mentioned are light and have lots of surface area for the wind to apply force to.

https://www.caltech.edu/about/news/leonardo-da-vincis-forgotten-experiments-explored-gravity-as-a-form-of-acceleration
In an article published in the journal Leonardo, the researchers draw upon a fresh look at one of da Vinci's notebooks to show that the famed polymath had devised experiments to demonstrate that gravity is a form of acceleration—and that he further modeled the gravitational constant to around 97 percent accuracy.

GRAVITY IS A GODDAMNED LIBERAL CONSPIRACY!!! WE COULD FLY THROUGH THE AIR ANY TIME WE WANTED!!! DON'T BELIEVE THE LIES SHEEPLE!!!
🇺🇲🦅🎆

"The ancient wisdom."

How do we know that lots of people didn't figure this out & then got on with their lives? Because there was no way for them to tell all the other people in the world, we'll never know, or if they wrote it down it's been lost, so likewise we'll never know.
Is hard to imagine what the world was like before mass literacy and mass communication.

Friction would like a word

This is true on earth. If you have objects of the same shape and different weights and you drop them from high enough to reach terminal velocity, the heavier one will have a high terminal velocity through air and reach the ground faster.
The "in a vacuum" thing is where this goes wrong, but I don't think homeboy really knew about space or vacuums.
- no. Gravity is consistently pulling at 9.85m/s regardless of the size or density in an object.
  Terminal velocity is reference to the air resistance and buoyancy affect on an object in freefall. This has nothing to do with the mass or size of the object, but it's air resistance.
  https://openstax.org/books/college-physics-2e/pages/2-7-falling-objects
  Gravity is (mostly) consistent across the planet and will always pull the same force regardless of the object in question.
  
  Gravity is consistently pulling at 9.85m/s regardless of the size or density in an object.
  Any object with mass has gravity
  Say the moon was falling to earth
  Would the earth not be drawn in space towards the moon as it fell?
  The moon and earth would collide at a rate faster than 9.85m/s?
  
  https://physics.stackexchange.com/questions/75942/terminal-velocity-of-two-equally-shaped-sized-objects-with-different-masses
- Not really always, because of buoyancy. A balloon of volume V displaces the same amount of air weather it's filled with air or lead, but in the former case the force is significant.

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