Recent comments in /f/explainlikeimfive
[deleted] t1_j6jnpjj wrote
pierrekrahn t1_j6jnfr8 wrote
Reply to comment by JerseyWiseguy in ELI5: Why aren’t all roads just.. straight? by koobtooboob
Also, more basically, the globe is a sphere. It's impossible to have all straight lights in a ball. They would be unnecessarily close at one part and unreasonably far at another part.
aspheric_cow t1_j6jndhd wrote
Reply to ELI5: Why do european trucks have their engine below the driver compared to US trucks which have the engine in front of the driver? by Naofumitarddv
Europe has a limit on the total length of the truck+trailer. So a shorter cab allows for a longer trailer. The US has a limit on the length of the trailer, but not the cab, so the cab can be as long as you want. And a longer cab allows for better aerodynamics and more room inside, which is especially important for American long-haul trucks because most drivers live in the cab.
EeJoannaGee t1_j6jn652 wrote
Reply to ELI5: Why do european trucks have their engine below the driver compared to US trucks which have the engine in front of the driver? by Naofumitarddv
Trucks driving in small streets in centuries old cities need more manoeuvrability than trucks driving in newer cities build for cars. Different things are needed, you need more literal space for the engine to be able to be in front instead of below.
MiloFrank76 OP t1_j6jn0z3 wrote
Reply to comment by MissFred in ELI5 Why is desalination so hard? by MiloFrank76
Thank you for this perspective.
Mackie_Macheath t1_j6jmv09 wrote
Reply to comment by Likes_The_Scotch in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
You actually can but you have to be pretty good at soldering.
RusticGroundSloth t1_j6jmh5c wrote
Reply to comment by jimmysofat6864 in ELI5: Why are contactless payment methods faster than inserting the chip? by jimmysofat6864
I've got 2 semi-educated guesses on why this is.
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Using the chip there's a decryption process to get the data off the chip. The terminals in use aren't exactly using high-end processors, so the decryption could take a bit longer. With the contactless payment it's just exchanging a small amount of data without the encrypt/decrypt taking up time.
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The time it takes to contact the payment processor and get authorization. I've noticed a significant difference between a Wal-Mart and a Smith's (Kroger) in my town. Both of them don't take contactless payments so this is with the chip. The Wal-Mart takes ~10 seconds to return an authorization, but the Smith's takes about 3 seconds. Same card, even looks like the same PIN-pads on the self-checkouts. Could be faster network/Internet speeds at the store, could be differences in how they process the payments (I wouldn't be surprised if Walmart has some centralized setup to handle that rather than each store "calling" the credit card service)...hard to say, but there are a lot of variables beyond just chip vs NFC.
chriswaco t1_j6jmgof wrote
Reply to comment by SelectTadpole in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
They were fine. Not high fidelity or anything, but fine. The noise of the engines was the biggest drawback and the earplugs weren't always comfortable.
konwiddak t1_j6jmd3k wrote
Reply to comment by RhynoD in ELI5 Why is desalination so hard? by MiloFrank76
In any real world plant that operates via evaporation, most of the energy used to boil off the water is re captured via the heat exchangers used to condense the steam back into water. This heats the incoming water. (Most are multi stage running different parts at different temperatures/pressures.) Overall its a pretty efficient process, with reverse osmosis a bit more efficient.
However the amount of water that we use for not drinking purposes, irrigation, washing e.t.c is massive.
nrron t1_j6jm8vv wrote
Reply to ELI5 why do your eyes adjust so fast to bright light but so slowly to darkness? by melig1991
Your eyes have to adjust quickly to bright light to prevent damaging them. That’s why going from a dark room into bright sunlight hurts your eyes. Adjusting to darkness takes longer because there’s no I’ll effects to it being slow to your vision.
berael t1_j6jm8qy wrote
Reply to ELI5 why do your eyes adjust so fast to bright light but so slowly to darkness? by melig1991
Your pupils clamp down quickly because very bright light can damage your eyes. Kinda an "emergency lockdown" situation.
They can expand more slowly to be cautious of overdoing it.
TheDefected t1_j6jm7h3 wrote
Reply to ELI5: Why do european trucks have their engine below the driver compared to US trucks which have the engine in front of the driver? by Naofumitarddv
There's a max length, so a lot of Euro trucks have to keep the tractor unit as short as possible to avoid eating into their quota.
sim-o t1_j6jm2rq wrote
Reply to ELI5: Why do european trucks have their engine below the driver compared to US trucks which have the engine in front of the driver? by Naofumitarddv
One reason is that the total length of the truck and trailer is shorter. I think UK/European roads are more suited to that configuration
MiloFrank76 OP t1_j6jlufl wrote
Reply to comment by dkf295 in ELI5 Why is desalination so hard? by MiloFrank76
Thank you. Do you think the need for fresh water increases in the future, that we'll figure out something?
firelizzard18 t1_j6jlb2e wrote
Reply to comment by Freedom-No-781 in ELI5 - When losing weight, why is it common to hear "burn more than you consume" in reference to calorie intake. if you consume" 1000 calories, how do you burn 1500? by Freedom-No-781
You burn calories by living. If you exercise, you burn more. If you consume zero calories you will starve because you burn 1500-2500 each day (depends on the person) by living. If you know your basal metabolic rate (how many calories you burn per day) and you eat 500 calories less than that number, you’ll lose about a pound per week.
Envelope_Torture t1_j6jl40g wrote
Reply to comment by Caucasiafro in ELI5 Why is desalination so hard? by MiloFrank76
Most large scale desalination is reverse osmosis, which produces a very salty brine rather than solid deposits of anything. Further processing and refining of minerals from this would also be very resource intensive as well as complex. There is a lot of research going on in this area as well.
thecaledonianrose t1_j6jkrk9 wrote
Reply to comment by sharrrper in Eli5....can you dig a well anywhere and hit water...and how did the early ranchers in the West know where to dig for water. Especially in the really dry areas? by pinkshrinkrn
Mm, true. And it isn't as if you limited it to 'potable water,' strictly speaking.
Goodperson5656 t1_j6jkk5d wrote
Reply to comment by redditlurker67 in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
I thought they had the 2/3 jack option so people wouldnt steal the headsets?
SelectTadpole t1_j6jkk1f wrote
Reply to comment by KeetoNet in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
Oh shit. I've used them before, then! How fun. I don't remember it sounding too bad but I wasn't really thinking about it, either. Nor did I have much of an ear for music quality at the time.
On the other hand I do remember thinking "so this is how they invented dubstep" when 80's pop was playing at the same time as the very loud machine making crazy noises.
samuarichucknorris t1_j6jkjii wrote
Reply to ELi5 : If you can access a website, why cant you steal the source code and make a 1:1 copy of it? by 13lettersinhere
What your browser barfs back is just HTML / CSS.
Unless the website is 100% client side, then no you cannot just copy the HTML source and rip off the website.
There is an entire tech stack / ecosystem behind the scenes that reacts to what data your sending back over the wire and in turn you get a response containing the HTML. Your "abstracted" away from everything that isn't in the presentation layer (source code wise).
KeetoNet t1_j6jk4up wrote
Reply to comment by SelectTadpole in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
Terribly.
Of note, these are still used in MRI machines. Presumably because of the whole 'no metal in the giant magnetic field' thing.
d4rkh0rs t1_j6jk32l wrote
Reply to comment by Fred2718 in ELI5: What exactly is Random Access Memory? by FilmFrench
I just missed the tape era(unless Sinclair and Commodore count).
My understanding was the original systems had to read each header without a good index allowing them to jump to record X.
It sounds like your systems were a bit more advanced.
I bow to your greater experiance while wishing we could hear from the 50s and 60s.
koolguykris t1_j6jk1zs wrote
Reply to comment by saberline152 in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
I flew in 98 from France to the states as a.... 4 year old? And all I can remember from that flight was a large screen where they played flubber on repeat.
faaizk t1_j6jjz2l wrote
Reply to comment by mbrady in eli5: Why do most airlines still use 2-pin audio jacks for the in-flight entertainment systems on their planes? by JJGLC92
that’s incredible! i find this kind of analog tech just so fascinating
fiendishrabbit t1_j6jnu4y wrote
Reply to ELI5: Why do european trucks have their engine below the driver compared to US trucks which have the engine in front of the driver? by Naofumitarddv
European conditions and regulations favor a cabover configuration:
P.S: Meanwhile a conventional truck is more aerodynamic, it's easier to access the engine and it's a smoother ride since you're behind (and not over) the forward axle. So it's a favored configuration when you have longhaulers on long open roads (like much of the US).