Recent comments in /f/explainlikeimfive

thebigger t1_iy8ussc wrote

> As people have stated, salted ice melts faster than non-salted ice because the freezing point is lowered.

Is that true? The freezing point isn't lowered, per se. Adding salt to ice is adding weight to ice, just like stepping on ice. When you step on ice you compact it, and a bit of it melts. That bit that melts then mixes with the salt and the process begins.

Certainly the freezing point is lowered, but I'm not sure that is relevant here, and it isn't why the ice melts AFAIK.

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thebigger t1_iy8ug7h wrote

Are you sure about that? Certainly if you're comparing ocean water to lake water you are correct, but adding salt to ice would be adding energy and slightly increase the temperature if I'm not mistaken.

The role the salt plays is that it facilitates the melting of the ice more quickly, which is colder, but I'm not sure that adding salt makes it colder.

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tdscanuck t1_iy8ueeg wrote

Ultracapacitors are terrible at storing large amounts of energy, compared to batteries.

They're very good at charging/discharging quickly, and going through lots of cycles, but at best they can only hold something like 1/300 to 1/1000 of the energy that an equal weight lithium battery can.

Range extension requires storing a lot of energy...batteries are reasonable for that. Hydrocarbons are extremely good. Capacitors are awful.

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shaokim t1_iy8trca wrote

I'm not sure if your premise is correct. In hypovolemic shock, central venous pressure (which I think is a useful proxy for preload) will decrease or remain equal because of lower circulating blood volume. I'm not sure if your reference to "blood cells" is of relevance in this particular bit of physiology.

Total intravascular volume goes down, therefore preload goes down. I think it's roughly as straightforward as that, in any case I don't think it would increase.

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thejml2000 t1_iy8t701 wrote

For others here (from): > In December 1998, the IEC addressed such multiple usages and definitions by creating prefixes such as kibi, mebi, gibi, etc., to unambiguously denote powers of 1024.[10] Thus the kibibyte, symbol KiB, represents 2^10 bytes = 1024 bytes. These prefixes are now part of the IEC 80000-13 standard. The IEC further specified that the kilobyte should only be used to refer to 1000 bytes. The International System of Units restricts the use of the SI prefixes strictly to powers of 10.

Also: The ISO/IEC 80000 family of standards was completed with the publication of Part 1 in November 2009.

For us old timers (and a lot of documentation), KiB is still new. Indeed, KB is still said used to reference 1024 bases instead of kB which is 1000… and that’s why that IEC 80000-13 was published, to clear up that confusion and add KiB as a documented and remove ambiguity. It didn’t matter so much with low amounts, (64000 vs 65536 bytes for instance) but now that it’s used for petabytes, it’s kind of a big difference.

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AlchemicalDuckk t1_iy8su86 wrote

It really depends on context and usage, at least historically. The prefix could mean decimal (e.g., 1 kilobyte = 1000 bytes) or binary (1 kilobyte = 1024 bytes). You commonly would have seen the former on things like hard drive sizes and network speeds. So for instance, a 1 gigabyte hard drive would really be 1,000,000,000 bytes.

The IEC defined a new set of prefixes to get around the ambiguity. For instance, the kibi- prefix means 2^10, so a kibibyte is 1024 bytes.

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nesquikchocolate t1_iy8r88c wrote

Safe exposure to noise levels is measured in doses over duration. "Softer" noise over a long duration can be just as damaging as louder noise over a shorter duration.

Active noise cancellation can reduce this compounding effect over longer durations, but as you've stated already, there's little benefit to funding the medical trials needed for certification, when your competitors will undercut you on price and release products more often than you ever could.

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daniuwur t1_iy8qron wrote

Those usb sticks are built by grouping memory chips on a pcb.

Imagine how hard the logistics would be if instead of a standard 6 pack beer we had 7 packs, 5 packs, 11 packs, 13 packs

In thus case a 6 pack is a memory module of 8gb, if you ask the manufacturer to build a 42.069 gb usb they will say "i can do either 32 or 64, im not going to design and manufacture a special design just for you (i can do it, but it will cost you more than making a 64 gb version)"

Edited because 40 is a multiple of 8 lmao

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nesquikchocolate t1_iy8qqw0 wrote

Yeah, no... That's definitely wrong. Active noise cancellation (ANC) reduces the sound energy which makes it to your eardrum.

To claim that it works medically, though, takes years of medical trials under rigorous standard. Very few companies have the desire, drive or funding to commit to such an endeavor, and it won't help their bottom line either, because now other companies can use this research to support their own claims about protecting your hearing.

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Belbarid t1_iy8pr85 wrote

>I just don't understand how they can calculate this amount of difference in repayments..

Amortization tables and calculators. U.K. is probably a little different, but in essence an amortization table shows the relationship between your total mortgage amount, your interest rate, your remaining principle amount, your loan length, and your monthly payment. Change any part, such as your interest rate, and the table can be rebuilt showing the effect of that change. If your interest rate goes up, the table will show how your payment is affected, based on how much longer you have on your loan and how much of the principle you've paid off.

Which leads me to a big piece of general advice. Overpay and make sure that your overpayment is applied to principle and is not applied to your next payment. Even small reductions in your principle can have a large effect on your length of payment, which in turn reduces the amount of interest you pay.

Find a good amortization calculator online and play with the numbers. Find out what happens if you overpay £50 per month, for example.

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Ippus_21 t1_iy8p3e7 wrote

Because it only makes it "sound" quiet, without necessarily reducing the actual sound pressure you're exposed to, and it provides no protection against v. loud or percussive sounds.

Tbf, some legit hearing protection also includes noise cancelling, or has other technology to let, e.g., normal speech filter through and just break off the peak decibels.

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