When you burn rocket fuel, it makes a bunch of hot gas. By pushing all that gas out of a (moveable) nozzle in one direction, it pushes the ship in the opposite direction.

ELI5:

It's like blowing up a balloon and then letting go of the neck. It flies off because every action has an opposite reaction. The balloon squeezes the gas out the neck, which pushes the balloon off in the other direction. This would happen in space with no outside air around the balloon too! We just use rockets instead of huge balloons because rocket fuel is a convenient way to bring up a large volume of solid or liquid fuel in a small space and then turn it into gas to shoot out the nozzle as needed.

As an extra precaution I advised my children to always place a hand on the car before inserting the hose to discharge any possible static through your hand and not at the fuel inlet.

It follows the same principle as attaching a grounding cable to an aircraft prior to fueling.

The gas tank isn't normally open. The engine contains the gas inside, but fueling potentially introduces vapor to the space outside the engine where there could be a spark and the explosion wouldn't be controlled.

>Pumping fuel into your car can increase the amount of pressure in the system, which can increase the amount of pressure coming out of the fuel pump - particularly when the tank is near full.

Hell to the no it can't. Pressure is *regulated*. Also, I haven't seen a carburated vehicle sold since the '90s. That little needle valve attached to the float will regulate flow more than it will regulate pressure.

~ Signed: Old guy that's rebuilt his fair share of carburators.

Confirm what, exactly? Engine oil does not freeze. It gets more viscous, but it doesn’t freeze. -10F is not that cold. It’s that cold most of January and February here in MN, and my Q5 TDI starts up every day.

Your engine oil will not freeze. WTF are you talking about? I live in MN. In northern MN it regularly gets well below zero. Last winter it was below -40F and my Q5 TDI started right up after sitting outside overnight. If the oil was frozen ( which it won’t), the engine wouldn’t even be able to turn over.

Even if it COULD freeze, it isn’t going to in the 5-10 minutes it takes to fill up your gas tank.

So much misinformation in the thread…

Archers definitely shot for accuracy and power, at relatively close range, and not in volleys. Volley fire was done in the age of gunpowder, and on TV and movies for dramatic effect. Having archers who would use different strength bows hold arrows is useless. That would just slow down and exhaust your archers. It's not like after years of practice they don't know how to shoot accurately. Combat with archers involved them firing at will, when in range, and covered by other troops, or in a defended position. They pretty much always fired straight at their target, as seen in nearly every contemporary depiction of archers.

So these archers would fire arrows at a target maybe 50ft away, as fast as they could. The targets would need to move up fairly slowly under shield cover, since it was a) terrifying and loud, and b) you needed to stay in formation or you'd get hit.

Ammo was definitely an issue. Armies would prepare tens of thousands of arrows before campaign.

From https://www.reddit.com/r/AskHistorians/comments/1e7xa3/how_expensive_were_arrows_and_how_many_did_your/

"When Henry V succeeded the throne, he immediately began restocking the royal armoury in the Tower of London for a foray into France. He set the fletchers of England to begin making arrows, and we have a record of a contract for 12,000 arrows that cost the Crown £37, 10s, which translates to about $25,000. Arrows were produced in sheaves of 24, and archers carried between 60-75 with them into battle. They were expected to be able to shoot about 12-20 arrows per minute (An archer who could shoot no more than 10 arrows per minute was considered to be unfit for military service. Each archer carried two sheaves of arrows in his quiver and the rest stuck in his belt for quick and easy access, though he may have stuck them in the ground when he was entrenched in a position (say, Agincourt.) Each archer could therefore only shoot for about 3.5-7 minutes with the arrows he had (which is NOTHING in a battle. Seriously, 5 minutes of shooting and you're outta ammo? That's crazy.), so there were wagons that were also filled with arrows, and young boys provided a constant transport of arrows from those wagons to the front lines."

That 12,000 was just one contract. He probably had many more contracts to supply his archers.

Battles in real life are nothing like on TV. Battles often lasted many hours, mostly involving small battles fought in short bursts. You'd have two lines of troops mostly marching or standing around trying to outmaneuver the other army, and a few small battles involving a few dozen men would pop up every now and then. One or two might die, one or two might get injured. Eventually one side would create a small gap, the other side might fill the gap stuff reinforcements. This goes on and on for a few hours until one side is too scared, tired, or injured to reform the line, the enemy will seize the gap, cohesion and order breaks down, and then you'd lose the battle.

In such a fight having skilled archers is very powerful. If you are standing 50ft from the enemy and getting shot at, you are stuck in that position, allowing your enemy to maneuver. It's very hard to advance under fire. If that's not enough, the archers might kill, injure, or terrify that part of the army and they may break and flee. Such a gap can be easily exploited for victory.

Not a single word of this is true. Complete made up bullshit.

I have to wonder if the added fumes from your idling automobile would make a detectable difference in the air quality of the average gas station environment.

We appreciate reports of questionable posts, given that we're a volunteer team.

The sign predates automatic stopping refueling nozzles, by many years.

Cars were significantly more dangerous in the early years, with very few regulations helping guide designers around safe refuelling practices.

I’ve heard this before…but I get in and out of the car regardless if whether it’s running, so why does that matter?

That's a falacy, though. You can't prove a negative like that.

Even if only 1 fire/explosion/loss of life occured due to possibly running the engine while refuelling, that sign could have helped.

There's no downside to the refueling station for posting that sign.

nah he'd say "undidstroopable" or something

> In super cold conditions (and I mean like -40°) it's actually recommended to not stop the engine while refueling as the engine oil could freeze in that time and the car not be able to start again.

Can confirm. I lived in Fairbanks,AK for a couple years. And when the thermometer dropped below about -10F, I kept the engine running.

The file name doesn’t have anything to do with the format inside. File extensions serve two purposes: mostly, they are there to help people remember the type of data in the file, and sometimes they are used by the desktop environment to sort files and decide which programs open them.

In fact, the program itself opens the file and checks the data inside the file to figure out what to do with it.

JPEG, GIF, WebP, are all very different. You can name the files whatever you want, but if you look at the first few bytes of data in the file, you can tell right away if you are looking at a JPEG file that’s name ends in .GIF

Probably not, they work on unrelated areas/receptors.

I wasn't aware of your second paragraph and now I feel like I learned something today. Cool.

This is actually a continued subject of debate/study among economists, but the leading theory right now is that it is driven by a taste for variety. In essence, a country may only be able to support three or four major car manufacturers, but there are millions of people in that country that all like different kinds of cars. The best way to continue to capitalize on economies of scale and still deliver on the widest variety of cars for your consumers is to trade between countries/manufacturers.

Are you renaming them after saving them to disk, or changing the URL to have a different name?

Some web sites offer the same file in multiple formats. Changing the URL means you're requesting the file in a different format, and some sites can oblige and actually give you the alternate formats.

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This is called the 'Dunning-Kruger Effect,' and while I'm not an expert on it, my understanding is that people experiencing it just do not have an awareness of what they don't know. They know enough of a thing to get by, and they have no cognition that there's more to know, and they use the power of rationalization to turn evidence of what they don't know into some other explanation. They're not wrong, someone else was, and so they were operating on faulty information, but this time they'll get it right.

I think Impostor Syndrome is a combination of things (again, these are just my understandings). One, just a general lack of personal security. There's a lot about the world that is designed to make us feel insecure so that we'll work hard to be able to buy things. There are literally whole industries built around it. Being insecure makes it very hard to feel like whatever knowledge you do possess is good enough because you're not doing good enough to get the thing.

Then you add an awareness that I think most people eventually have that you do not and cannot know everything, even for just one specific, non-personal subject. When that interacts with insecurity, it leads to devaluing the knowledge you do have because clearly there's so much more knowledge out there, so it gets really easy to say to yourself that you don't have the specific knowledge you need to do the thing in order to get the thing.

So in effect what you have is two people who are just kinda half-competently managing to get through life (which is the best any of us can really hope for), but one believes that their success is entirely of their own making because they lack external awareness, and the other believes they've gotten by entirely by chance because they have perhaps too much external awareness.

EDIT: I typed this too fast and there were a bunch of typos that I went back and fixed.

Upgrade to Photoshop 2021 (v22) or Photoshop 2022 (v23). What you're describing is a known bug in older versions of Photoshop. Photoshop 2020 and Photoshop 2019 had a bug where they could only open .jfif files if they were incorrectly renamed as .jpg.

Honestly sounds like a word Trump would use.

It’s call the Dunning Kruger effect. Essentially it says that those who are not competent in a skill will overestimate their ability because they literally don’t know what they don’t know. While people who are competent know how much they don’t know because of their proficiency.

It’s for this reason that it’s important to know that if you sometimes struggle with imposter syndrome you’re not an imposter. If you were, you wouldn’t care or know enough to experience it.