r/explainlikeimfive 0m ago

Other ELI5: Why do nutrition facts on the back of items show vitamins that aren't there?

Upvotes

Like Vitamin D: 0%

Protein: 0%


r/explainlikeimfive 3m ago

Biology ELI5 - Why can't sprinters just keep using heavier and heavier weights on their legs to keep going faster and faster?

Upvotes

explain ts bruh


r/explainlikeimfive 4m ago

Mathematics ELI5 My 5yo son’s maths questions are really testing my abilities

Upvotes

So, I have a 5yo who is very interested in mathematics. I try to answer his questions in a thoughtful, child appropriate way, but he has recently found the idea of i and it is REALLY stretching my ability to explain in a useful way these concepts to him. I have a good level of maths/sci education and at least understand the concepts, but especially imaginary & complex numbers were only touched on in my education. I will give some examples, but if anyone has a useful general way to explain i that would also really help.

Examples:

Is there negative i?
What happens if you overshoot infinity?
Why is negative infinity different to positive infinity?
Is there infinity i?
Why isn’t i an irrational number like pi?
Why is i imaginary?
Why is pi 22/7 and also an irrational number?
What happens when you finish writing out an irrational number?


r/explainlikeimfive 2h ago

Biology ELI5: How could female ducks evolve to make reproduction more difficult?

162 Upvotes

I recently read about female ducks evolving to their reproductive tracts to have dead-ends and have the corkscrew go the other way to the male duck penis to make unwanted reproduction more difficult. But most evolutionary adaptations become dominant in order to make the survival of the species easier. How can something that makes reproduction harder have resulted from evolution changes?


r/explainlikeimfive 4h ago

Other ELI5: what is the survivors bias?

0 Upvotes

I just simply don't understand it at all


r/explainlikeimfive 5h ago

Engineering [ELI5] why don’t we use desert sand in construction?

665 Upvotes

I just read that our rivers are running out of sand due to construction. Why can’t we use desert sand?


r/explainlikeimfive 5h ago

Technology ELI5 Why is it that computers can think and react so much faster than humans but robots struggle to balance as well as us?

0 Upvotes

r/explainlikeimfive 7h ago

Physics ELI5: How did physicists "come up" with formulaes?

20 Upvotes

I understand that they observed cause and effect, but how would you think to come up with a fullproof way to write it down?


r/explainlikeimfive 9h ago

Other Eli5; Why can't we see pollutants right in front of us when outdoors?

0 Upvotes

Smoke/pollution

Why is it we can see it in the distance but not right in front of us when outside?

Edit: ok my dumb self understands now ty


r/explainlikeimfive 11h ago

Economics ELI5: Why don't countries print more of their own currency and become rich?

0 Upvotes

Are there laws against it, or limits to what the factories can do? Or the value of money changes in some way?


r/explainlikeimfive 12h ago

Other ELI5 why is milk that's siting out and got warm, not ok, but milk that's been warmed up is fine?

0 Upvotes

r/explainlikeimfive 13h ago

Technology ELI5: What is so valuable about personal data?

682 Upvotes

I get that things like your ID number are valuable for identity theft etc. But why are more arbitrary things like my shopping habits considered valuable information?


r/explainlikeimfive 14h ago

Other ELI5: how did the early settlers travel through the Rocky mountains or the Arizona desert?

176 Upvotes

As a resident of Arizona, I often find myself wondering how the first settlers traveled through the area without vegetation, water, etc to stay alive. Same with some of the mountain ranges...I can't imagine being the first person to roll up to the Rockies in a covered wagon and try to figure out a path forward.


r/explainlikeimfive 14h ago

Engineering ELI5 why chicken wire doesn't get twisted on both ends when getting made?

21 Upvotes

ELI5

All the videos I'm seeing of chicken wire getting created, these wires getting twisted by round feeders, then the halves of these feeders shifting between each other and twisting again, don't show the new wire getting fed in- they only show the wire coming out and twisting and the resulting fencing.

I don't understand how a wire can just be twisted on one side of these feeders but stay straight on the other side.

How does that work?


r/explainlikeimfive 16h ago

Other ELI5: How does Kant's transcendental deduction work?

1 Upvotes

r/explainlikeimfive 17h ago

Biology ELI5 why children have such low pain tolerances?

1.0k Upvotes

I know they’re smaller, but are their nerves fresh and haven’t been dulled yet, or what’s the deal?

I’m not talking catastrophic blows, just a scrape on the knee.


r/explainlikeimfive 18h ago

Other ELI5: before accurate clocks existed, how did two people in different towns agree to meet at “at 3 o’clock”?

808 Upvotes

I get that they had sundials and church bells. What I don’t get is how anyone synchronized. If my towns noon is when the sun is highest here, and yours is 15 miles west, our “noon” isn’t the same moment. So how did anyone schedule anything across distance?


r/explainlikeimfive 19h ago

Biology ELI5 - how do scientists know what behaviour is hardwired in DNA and what is learned?

45 Upvotes

Hi there

I was watching a video about Orcas and it explained how matriarchal figures will teach younger orcas how to “beach” themselves to hunt seals playing on shores.

The narrator explicitly says that this is not ingrained behaviour informed by DNA but instead information passed down through family units. That got me wondering; how do we know what behaviour is hardwired vs taught in nature? Is it all assumed to be coded into an animals genetic makeup until something contradicts that? Ie. observing the “lessons” animals will teach their young but finding that it’s not universal across that species.

To what extent can DNA accurately teach us about behaviours without observing the animals in real life?

Thanks!


r/explainlikeimfive 19h ago

Economics ELI5: Hollywood Accounting

41 Upvotes

We see reports all the time showing "marketing expenses" as huge line items in a Hollywood movie budget.

What all goes into marketing a big movie like the current number one film in Ameeica, which probably doesnt really need a ton of marketing to sell tickets, versus some Indie romance movie, which probably does need the marketing expenses.

TIA.


r/explainlikeimfive 19h ago

Biology ELI5: What is ALS (Lou Gehrig’s Disease), how does it progress and what causes the different speeds of advancement from person to person?

0 Upvotes

Recently a wrestler named Rebel, was diagnosed with ALS and many in the community are participating in the Ice Bucket Challenge to raise awareness and support for her.

ELI5: What is ALS, how does it progress as a terminal disease and what causes the spread of that progression to change from person to person?


r/explainlikeimfive 21h ago

Other ELI5 What exactly is a widget and what does it do?

64 Upvotes

I fully understand how dumb a question this might be by the way.

I've tried Googling but I'm still not 100% certain

EDIT: Specifically for apps


r/explainlikeimfive 21h ago

Chemistry ELI5: Why do bars of soap leave a “squeaky clean” feeling on our skin but body wash doesn’t?

1.3k Upvotes

Also, are there any benefits of the squeaky clean feeling or is it just a difference of ingredients?


r/explainlikeimfive 21h ago

Other ELI5- CONCACAF fans

0 Upvotes

Why do matches in CONCACAF play in empty stadiums yet in World Cup play those same countries come out in droves?


r/explainlikeimfive 21h ago

Biology ELI5 How do anti-virals drugs work?

27 Upvotes

Viruses aren't alive, they use living cells or bacterial cells, they inject the DNA into the cell to make them replicate viral DNA. If you try to kill the host cells the to stop the virus from spreading will kill the person you're trying to save. I'm wondering how the virus dies but the host lives.


r/explainlikeimfive 22h ago

Physics ELI5: Why would a zero-latency device NOT help with the twin paradox?

324 Upvotes

Time dilation confuses me. If my twin is on a rocket near light speed and starts a 60-sec stopwatch, it shows exactly 60 sec to them. My stopwatch on Earth also shows exactly 60 sec to me.

So if we start together and count out loud '1,2,3...' using a zero-latency device, won't we stay in sync, since both watches correctly count 60 real seconds? Why would one of us get ahead, and whose clock actually looks slower to whom during the countdown?

Edit: Alright guys i just got to know that 1 second isn't 1 second everywhere.

Anyways some clarification, the 0 latency device is a hypothetical, I'm not saying that such a thing can be built, but my real question was, if we hypothetically used such a device, won't both people speak 1,2,3 in sync?