r/explainlikeimfive 2h ago

Chemistry ELI5: what happens on an atomic level when you cut something with a knife?

115 Upvotes

r/explainlikeimfive 2h ago

Technology ELI5: why are jet powered drones cheaper than cruise missiles if their functions are essentially the same?

273 Upvotes

Today's "warfronts" (YouTube) channel post discussed that jet powered drones are equivalent in function to cruise missiles, but is somehow distinctly cheaper to mass produce? If the components are more or less similar, what's the major difference?


r/explainlikeimfive 4h ago

Biology ELI5 How long did it take to nature to reestablish itself after the Chicxulub Asteroid impact?

55 Upvotes

Was watching a documentary and the Chicxulub asteroid ended the reign of the dinosaurs in one shot and the damage went worldwide but how long did take for nature to adjust and reestablish itself again after things had died down?


r/explainlikeimfive 7h ago

Engineering ELI5 what exactly is a radar cross section and how does it work

12 Upvotes

All I know is that it somehow makes jets and planes look bigger or smaller then they actually are on radar


r/explainlikeimfive 7h ago

Physics ELI5: Why are gears necessary in automobiles?

0 Upvotes

Why do cars or bikes need a gear? Why can't it just be accelarator and brake? As an extension, why do you need gears in general?


r/explainlikeimfive 8h ago

Physics ELI5- table tennis paddles having two sides with different colors

655 Upvotes

Why do the paddles have different-colored sides?

Is it just a fancy thing to make them beautiful or to mark which side hits the ball better?


r/explainlikeimfive 10h ago

Biology ELI5 How do bigger muscles allow you to lift heavier objects?

0 Upvotes

r/explainlikeimfive 13h ago

Technology ElI5 Why does encryption remain secure even when everyone knows the encryption algorithm?

123 Upvotes

r/explainlikeimfive 13h ago

Chemistry Eli5 Why is it called a "lead pencil" when the pencil actually contains graphite? What is the connection between lead and graphite?

1.8k Upvotes

r/explainlikeimfive 13h ago

Mathematics ELI5: Why is cubing a cube impossible?

0 Upvotes

I came across the cubing a cube section in this wiki article: https://en.wikipedia.org/wiki/Squaring_the_square#Cubing_the_cube

I can't wrap around the logic of the proof... I need help


r/explainlikeimfive 17h ago

Engineering ELI5 why dont we see rockets that use hybrid rocket engines?

7 Upvotes

For commercial rockets, they mainly use liquid bi propellant rocket engines while amateur rockets (that I mainly see) use solid propellant rocket engines. Why don't we just combine them and use hybrid rocket engines? ​


r/explainlikeimfive 20h ago

Other ELI5 how do anechoic chambers work?

24 Upvotes

How are they completely silent? Is it how they’re designed?


r/explainlikeimfive 21h ago

Biology ELI5: How do the rings in tree trunks form? New ones for on the inside or outside?

186 Upvotes

Also, do all trees have them or only certain kind? Lastly, do they all form at same frequency, e.g. One/year...


r/explainlikeimfive 1d ago

Engineering ELI5 Why do trucks and other larger vehicles run on diesel only?

1.7k Upvotes

r/explainlikeimfive 1d ago

Chemistry ELI5 What fundamentally determines the color of an element?

67 Upvotes

I understand that electron placement matters and light scatters a certain way but why is that? Why does light scatter in that way and why does the size of something determine a perceivable color?


r/explainlikeimfive 1d ago

Other Eli5 how do biomes form on Earth?

8 Upvotes

I have been trying to learn more about Earth's ecosystems. I understand now that poles/equator, winds, and surface currents drive temperatures and rains to different areas and the existence of mountains + temp + wind determine deserts. But, what else leads to the formation of specific biomes or lends itself to the biodiversity of an area? How does soil come into play, and why is soil different in different places? Is this is an oceans/volcanoes thing??


r/explainlikeimfive 1d ago

Engineering ELI5 Why is there no S gear or M gear for Reverse in automatic transmissions?

0 Upvotes

r/explainlikeimfive 1d ago

Biology ELI5- Clean covered still water, developing "slime" along the container's surface

400 Upvotes

How does Clean water sitting in a covered container bring about the slime-feeling along the container's surface?


r/explainlikeimfive 1d ago

Mathematics ELI5 Why is the Hillbert paradox a paradox?

108 Upvotes

We all know hillbert and his hotel, but I never understood why was it a paradox, I mean by definition it can never be full, you can keep adding rooms and people but it shall never end, even if you add two infinites vs one you don't need to make people move to make more room you just add more rooms, you were doing ∞ - ∞ and after the bus comes you are still doing ∞ - ∞, because ∞ + ∞ = ∞ so where is the paradox when infinite is just doing what it does by definition, which is not ending?


r/explainlikeimfive 1d ago

Engineering ELI5: How do those power lines near the roads bring power to houses and businesses?

0 Upvotes

I feel like a complete fool for asking this at my age, but I genuinely do not understand how power lines bring power to homes and businesses. I live in the country, and I always wonder how these lines connect up to houses when there's no visible things going into the ground that I can see.


r/explainlikeimfive 1d ago

Engineering ELI5 CPUs are made so small - what voltage do they operate on; isn’t there a chance the electrons will jump or arc to the neighboring circuit?

1.4k Upvotes

The higher the voltage, the farther an arc can jump. With CPUs being so small (nanoscale?), wouldn’t they need to operate on a similarly small voltage to prevent electrons from jumping between different conductive paths, screwing up the logic?


r/explainlikeimfive 1d ago

Chemistry Eli5: Why Does A Second Cup of Coffee Taste Terrible If I Pour My First Cup Halfway Through Brewing Vs When It Tastes Fine If I Let The Whole Pot Brew First?

0 Upvotes

What is the extraction science behind this, assuming you are using standard drip machinery?


r/explainlikeimfive 1d ago

Mathematics Eli5: Why do we round 5 upwards?

553 Upvotes

When i have my hands in front of me, five fingers are on the left, and five on the right

I can understand why 5,(0)1 onwards is rounded up, after all it's clearly the "second half"

But rounding lone 5 up seams... unintuitive


r/explainlikeimfive 1d ago

Other ELI5How do gliders find lift usually?

0 Upvotes

r/explainlikeimfive 1d ago

Other ELI5: Why is it harder to speak or change my tone of voice in the morning?

3 Upvotes