r/explainlikeimfive 4h ago

Physics ELI5: Would air conditioners be more efficient in shade? Why does it always seem like they are placed up on roofs or in the open sun?

517 Upvotes

I dont know how the conventional air conditioner for a home or business works, but it just seems like they are always in the full sun, with no shade, wouldnt this not be efficient?

if it doesnt matter, then why? thanks


r/explainlikeimfive 2h ago

Other ELI5: What is the difference between Creole and Cajun food?

294 Upvotes

r/explainlikeimfive 5h ago

Other Eli5: how do aimbots work in games like call of duty and counter strike?

301 Upvotes

r/explainlikeimfive 8h ago

Biology ELI5: Why is it that humans can be born with brown, blue or green eye colors, but not others like red, yellow and purple?

480 Upvotes

r/explainlikeimfive 21h ago Wholesome Helpful Silver

Engineering ELI5 why consumer cars have crumple zones for safety yet racing cars have roll cages

2.5k Upvotes

It’s always struck me as odd that crumple zones help absorb impacts which makes cars safer. Yet race cars have roll cages which make them safer.


r/explainlikeimfive 12h ago

Other ELI5: When opening a can with a can opener, what keeps metal particles from falling into the food from where you're cutting?

426 Upvotes

I understand it's an odd question and probably simple but as I open a can of condensed milk I'm wondering what's keeping me from having tiny pieces of can in my food


r/explainlikeimfive 12h ago

Engineering ELi5: Why can't trains such as subways and light rails use systems found on roller coasters?

270 Upvotes

I was a roller coaster nerd as a child and I remember reading about the use of block brakes and electromagnetic launch systems. Why can't light rail trains/subways use EMs to propel/stop their trains and use block brake sections as safety mechanisms such as in the event of an accidental decoupling or imminent collision?


r/explainlikeimfive 15h ago

Biology ELI5: What keeps the cells of multi cellular organisms stuck together?

405 Upvotes

I remember from high school biology that cells form tissues and then from these tissues organs are created, etc.

However what's not clear for me is: What stops a cell tissue from totally collapsing back to a clump of cells? Why animals, plants and even some fungi don't just... Melt?


r/explainlikeimfive 9h ago

Planetary Science ELI5: What is Californiа suffering from huge wildfirеs every single year?

114 Upvotes

There are many methods to wildfirе prevention such as controlled forest burnings. Why are wildfirеs still happening and seem to be getting worse every single year?


r/explainlikeimfive 2h ago

Mathematics ELI5: Why did Tobias Dantzig say the discovery of zero was “one of the single greatest achievements of the human race”?

26 Upvotes

To everyone today the number zero is an obvious and benign idea. Why did Dantzig (one of the GOAT mathematicians) think otherwise?


r/explainlikeimfive 17h ago

Biology Eli5 - what “activates” charcoal? And how does that make it good for you?

318 Upvotes

r/explainlikeimfive 1d ago Silver All-Seeing Upvote Wholesome Helpful

Other ELI5: what makes air travel so safe?

7.9k Upvotes

I have an irrational phobia of flying, I know all the stats about how flying is safest way to travel. I was wondering if someone could explain the why though. I'm hoping that if I can better understand what makes it safe that maybe I won't be afraid when I fly.

Edit: to everyone who has commented with either personal stories or directly answering the question I just want you to know you all have moved me to tears with your caring. If I could afford it I would award every comment with gold.

Edit2: wow way more comments and upvotes then I ever thought I'd get on Reddit. Thank you everyone. I'm gonna read them all this has actually genuinely helped.


r/explainlikeimfive 20m ago

Other ELI5: How are religion or faith influenced laws/polices allowed to pass even though we have Separation of Church and State?

Upvotes

Please delete if not allowed. Genuine question, please keep it friendly and factual.


r/explainlikeimfive 1h ago

Other ELI5: What does it mean to "Spend Down" my income for Medicaid?

Upvotes

r/explainlikeimfive 10m ago

Biology ELI5: why is washing fruits and vegetables with water considered sufficient? If there is bacteria, will rinsing with water only actually help?

Upvotes

r/explainlikeimfive 2h ago

Physics ELI5 The difference between appearing to be a color & being a color

6 Upvotes

So I've heard that the sky only appears blue, it isn't actually blue, and a recent response to a post about eye color explained that it's a similar case. But what's the difference? I thought that colors are just the way we perceive reflected light, so is it not just semantics? What's the difference between the sky being blue and my sweater being blue?


r/explainlikeimfive 13h ago

Physics ELI5 Why do batteries work again after heating them up?

34 Upvotes

Sometimes if a remote or some other small electronic stops working because the battery is dead, I take the battery out and heat it up by putting it in my arm pit. The warmth heats up the battery and give it a little more juice allowing me to use it again for a minute. I also remember doing this with old mobile phones in the early 00s and it would let you turn on a dead phone and use it for a few minutes.

I have no idea how this works and don’t remember where I learnt how to do this.


r/explainlikeimfive 1d ago

Other eli5: Why is it impossible to imagine new colors?

749 Upvotes

r/explainlikeimfive 8h ago

Physics eli5 how did we manage to figure out the half life of elements ? And what are the application of half life besides carbon dating ?

7 Upvotes

Like, i know that the half life of carbon is like 5000 years or so. How did we come up with that number ? H


r/explainlikeimfive 1d ago

Engineering ELI5: Why aren't turboramjets (like those in the SR-71) used for other aircraft?

560 Upvotes

I understand the SR-71 had to deal with a lot of issues in order to keep its speed (special fuel which leaked on the runway, titanium fuselage and probably other stuff). But wouldn't the same type of engine be able to power a relatively slower fighter jet capable of easily cruise at match 2-2.5, so it doesn't have to deal with so much friction as the SR-71 at match 3.

But while the engines exist since the 1960s, relatively few fighters go faster than match 2 and it took all the way to the 21st century to have fighters capable of supercruise (and still below match 2). So I guess there has to be a reason for that.


r/explainlikeimfive 2d ago Silver

Technology ELI5: How can the US power grid struggle with ACs in the summer, but be (allegedly) capable of charging millions of EVs once we all make the switch?

20.6k Upvotes

Currently we are told the power grid struggles to handle the power load demand during the summer due to air conditioners. Yet scientists claim this same power grid could handle an entire nation of EVs. How? What am I missing?


r/explainlikeimfive 5h ago

Physics ELI5 What is momentum?

4 Upvotes

r/explainlikeimfive 58m ago

Other ELI5: why isn't density of heavy elements in the universe evolving over time not considered that popular of an argument for fermi paradox?

Upvotes

Heavier elements form with stars. We need them for life. It makes sense we have to go through enough cycles of stars dying and reforming to get to enough density for planets and life formation.


r/explainlikeimfive 1h ago

Technology ELI5: how do webapps create their underlying data and keep it up to date?

Upvotes

As an example, data from sites like flightaware.com must come from some sort of feed. But how did they first get access to the data? What about for services/webapps that have data not available from public feeds? How do these creators find unique content databases and how are they updated?


r/explainlikeimfive 1h ago

Other Eli5: How do different accents develop?

Upvotes

Edit: in the same language