“Common sense” is a colloquial term for knowledge that should be obvious.

Don’t sleep on the train tracks.

Don’t tease a bull.

Don’t drink toilet bowl cleaner.

Things that you, a thinking human with a functioning brain, should be able to just know without having to be taught specifically.

Of course it’s frustratingly uncommon sometimes, as the number of non-suicide train related fatalities would suggest.

Have you tried saying “Please” ?

Common sense generally refers to actions, thought processes etc. which are obvious, generally understood by the majority of a given demographic, and require little to no external explanation.

Really surprising how quickly this converges! I'd have thought we'd get 2 binary digits per step, not 4ish decimal!

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🎶 These are the only ones of which the news has come to Harvard. And there may be many others but they haven't been discovered🎶

In step 0, z²=4

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Not quite true as you put it, but the general principle applies. It's about voltage stacking and the same current being drawn from multiple sources.

Think of it as a slide going from the top of a building to the road below. You have a number of people that want to slide down (that would be the load). If you have one huge slide, the people will be hurting each other as they descend. Therefore, you add more paralel slides (batteries) so they can redistribute themselves and be less cramped (less overloaded system). By adding more batteries in series, you make the slope more steep so the people get down faster (more force to "push" them).

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As mentioned, a calculator will typically do it a bit differently. Usually numbers are stored in floating point format. 40 wouldn't be stored as "40", but as 1.01*2^5 where 1.01 is a binary number. 1.01*2^5 = 101000 in binary which is 32+8=40 in decimal.

The square root of a product of two numbers is the product of square roots: sqrt(a*b) = sqrt(a)*sqrt(b). To calculate the square root of 2^(n), we just need to divide n by 2: sqrt(2^(5)) = 2^(5/2) = 2^2 * sqrt(2). The calculator knows sqrt(2), so it only needs to calculate the square root of 1.01 (in binary), or more generally any number between 1.0 and 1.111... = 10 (i.e. 2 in decimal). The smallest and largest number only differ by a factor 2. You can make a few entries in a table to use as starting values, or just use the same value for all cases - it won't be that far off anyway. Do a few steps of the method I showed, multiply the result by the square root of 2 if needed (if the original exponent was odd), combine it with the integer powers of 2 (here 2^(2)) and you get the square root.

https://the-gist.org/2020/07/new-elements-island-of-stability/

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It's to do with international regulations around "Fixed" and "Replaceable" battery packs which haven't changed much since Li-ion batteries first were used in devices.

With Fixed the rules about how thick the container the battery is in is a lot less restrictive, Also you don't have to worry too much about sparks and shorts with fixed batteries.

With "removable" batteries you have to have certain thickness of container, space around the pack to insulate it from the rest of the device/vehicle, also access door has to conform to certain standards. As well as precautions to stop sparks and shorting when replacing batteries,. all of which adds weight for not much in return.

BMW did have a "battery replacement concept" :
Where you drive the BMW EV into a bay. The base then open up and a robotic grabber unbolts the battery pack from the bottom of the vehicle and takes it to an underground charging area and another freshly charged "pack" is then installed in it's place.

So you can either buy batteries with the car for an added upfront payment and charge them at home like normal.

Or get a "subscription style" yearly package, where the vehicle is cheaper to buy initially, but you don't "own" the batteries in the car, and the entire battery pack is replaced with a fresh/nearly fresh set of batteries every time you need to recharge.

Because there are domestic rights and privacy laws that have to be abided by that countries don't follow abroad. Also, foreign intelligence is very different tactics/skill-set from domestic. Tactics used abroad to get information wouldn't necessarily work, and they may prevent successful prosecution of crimes because they violated rights, didn't properly collect evidence, etc.

Is there anywhere I read about that "island of stability" in somewhere layman terms? That sounds interesting.

The periodic table is open at the bottom.

We have found the first 118 ones and filled up the top 7 row in the periodic table.

People are actively working on getting started on the 8th row and beyond. The problem is that all these elements are unstable. And the last few ones that we "discovered" were already so unstable that they only existed for a tiny moment before decaying.

It gets harder and harder to make them as we go along and what you get out of exists for shorter and shorter amounts of time.

There is expected to be a region deeper down in the periodic table where elements become more stable again. But that is only relative to all the other stuff around it.

Don't expect anyone to come up with a magic metal tomorrow but don't be surprised if at some point in the near future you read an article about a new element created in a lab.

There is also the possibility of making stuff out of things other than combinations of protons, neutrons and electrons as our elements are.

Don't expect anything there that will freely exist in nature and that you can touch with your won hands, but the possibility for stuff to exist however briefly outside the normal domain of chemistry is there.

Most sci-fi stories either invoke magic or wave their hands or don't discuss at all how their wonder materials allows for timetravel, ftl, anti-gravity or ist just incredibly hard and unbreakable.

That is not something we should expect from any new elements or undiscovered particles or matter.

It depends very much on the service provider.

When you receive a message, it's a copy of the original message the sender wrote. The sender might keep a copy of it or they might not.

The server that sent the message on might also keep a copy, or not.

The email on your computer or phone is usually another copy downloaded from your mail service.

Deleting an email you received will usually move it to a separate trash folder so you can get it back if you change your mind. The mail service you're using may also have its own similar function so they can recover deleted messages even if you empty your own trash.

Also, the person who sent the email can delete their copy, and it goes to their recycle/trash bin. And the service they use probably has the same thing.

Also, there may be backups of any of these systems, each with a copy of your message.

So deleting an email in one place does not necessarily delete it everywhere.

Okay if it's not a battery then it is just a cell.

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All EV vehicles and hybrids use a battery "pack" that pack is made of groups of individual smaller batteries.

A few things good to know is that each battery alone only puts out a little bit of power somewhere between 3 and 4 volts.. But that's not enough to move a whole car, so you string lots of batteries together and now it's 200, 300, even 400 volts.

Normally these are put together in groups, and you can have multiple groups in a single car battery.

But these batteries are also flammable if they're damaged. Much like a phone or laptop battery... But thoes don't normally move at 60mph, and are just one battery not hundreds together. So they need to be protected..

So you put the batteries inside a armored battery box under the car normally. Lots and lots of batteries in this box means the only way to fix them is to remove the whole box and in many cases, remove the whole group of batteries that have one single dead battery in it. And replace the whole set.. Since they're fused together it can be difficult or impossible to safely and properly replace a single battery cell.

There are lots of comments pointing out scooters in Asia with replaceable batteries... Understand the power demand on a scooter carrying two people is substantially lower than that of moving a modern American car. Modular and removable batteries really are not viable in a car without equiptment to do so, and the COST would be higher.. If a company did make a car with replaceable batteries let's be honest, they would 100% make the batteries a loaner you pay monthly or yearly to use, with the ability to exchange it at locations... But if you didn't pay, your loaner battery presently in the car would stop working. The other issue is that batteries are heavy, and often become structural to the car. To be removable means they can't be secured to the vehicle in the same way, and the car would need to be more reinforced to not require the pack for structural support. It causes a ton of engineering issues that just don't matter to a little scooter. And this is still side stepping that battery packs are liquid cooled, it's not just two little connectors from the battery to the car.

TL;DR often you CAN replace a cell group with a single field battery in it. But it still requires removing the whole battery case from the car usually, so it's expensive. Other ways of doing this would be less SAFE for the vehicle owner for a bunch of reasons. And safety and reliability are prioritized instead.

My suspicion is that the user wouldn’t have any way to recover it but Google could if they had some reason to (like, say, a nice letter from the FBI). So it depends a lot on what exactly you’re trying to avoid.

Whenever you find yourself scratching your head wondering why they built it the way they did there is really only one answer, and that is cost. It cost more money.

A company called Better Place tried that in Israel. It did not work well. Also, DC Fast charging can work on any EV, while a battery swap will only work on one specific brand of vehicle. Imagine if a Ford could only be refueled at a Ford gas station.