this post was submitted on 09 Apr 2025
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Uranium generates that energy by fission. The hydrogen in sugar could generate huge amounts of energy if fused.
And this boulder could generate huge amounts of energy if I pushed it up to the top of Mt. Kilimanjaro and let it roll down.
44 upvotes and 0 downvotes for a comment that doesn't understand that energy density measurements like this tend to measure the useful energy of a system.
It's disappointing that natural selection didn't figure out fusion.
It figured out photosynthesis instead. Why do your own fusion when you can just take advantage of the fusion that's already happening?
There is still time
I mean, technically it already has.
It's good it didn't, otherwise it's possible that all the hydrogen in the ocean would be fused into helium by now
Well, more likely it would significantly heat up earth due to the amount of energy released first, cooking everything/starting an endless cooking->extinction->cooling cycle
On the fusion planet: "Man, can you imagine if early life figured out how to make poisonous oxygen gas?"
*in a silly high voice due to all the helium
We have fusion (hydrogen) bombs. We just haven't figured out how to maintain and efficiently harness it for energy.
How much more energy would you get if you fused uranium?
Using the rule of thumb, anything heavier than iron requires energy input to fuse. So you lose energy fusing uranium.
Serious answer: A huge negative amount. Anything above iron requires energy to fuse (which is why it produces energy from fission.) and I'm pretty sure nothing with 184 protons could be stable enough to count as being produced - the nuclei would be more smashed apart than merging at that point.
Ask Hiroshima and Nagasaki.
In alphabetical order.
Edit: oops, those are fission, my bad
Those are fission. Fusion bombs don't fuse uranium. They use a fission bomb to fuse Lithium.
Fusion bombs use a fission bomb to fuse Hydrogen, which is why they're called H-bombs.
Look at all these nuclear scientists on Lemmy.
Sorry I meant Lithium Deuteride.
6Li2H
https://en.m.wikipedia.org/wiki/Thermonuclear_weapon
I mean if we really want to be technically accurate here, the lithium is just a moderater for the hydrogen isotopes to fuse.
But for me it gets fuzzy when looking at the reaction.
LiD is 4 protons, 8 neutrons. Add a new neutron, and bam, you have 4 protons and 9 neutrons. But that's where it gets weird to me. The lithium needs to decay or something into a tritium and dueterium which forces the tritium to fuse with the existing dueterium in the LiD molecule? Clearly the neutron has enough energy to transfer into one of the atoms to increase the chance of tunneling actually occuring.
The only real purpose of the lithium deuteride is that it's a dry, shelf-stable, room-temperature fuel. The very first hydrogen "bomb" (actually a building-sized device) used supercooled liquid hydrogen as the fusion fuel, but this was obviously not practical for a deliverable bomb.
I get that part, it's still the reaction I can't wrap my head around mainly because I don't understand how chemistry is any different than alchemy.
I know that lithium itself doesnt fuse to create He+T+D, and I know it can't undergo fission. Since lithium isn't left over, and lithium-6 and 7 are stable, does that mean the neutron with extremely high kinetic energy really knocks like two of the LiD mokecules into each other, causing dueterium -dueterium fusion resulting in He4, and the Li6 gets more neutrons that for it to be come unstable enough to decay into tritium or deuterium?
How about a nice game of Global Thermonuclear War?
For that matter, even the Nagasaki bomb ("Fat Man") didn't use Uranium at all - its fuel was Plutonium.
Oh, they do, but not as the primary or secondary. You can wrap depleated uranium around the core to capture fast neutrons that are leftover from the rest of the process. Changing the number of layers is how you can dial in a desired yield.
Damnit, you're right and I'm wrong!
That's fissed, not fused.
I stand corrected, because I done forgetted.
and all would generate the same if thrown to something capable of lossless e=mc^2 conversion (maybe a black hole)
sadly black holes go to something like 42% conversion (source: some minute physics video i think)
That's quite interesting. Is it because of the light produced when the materia starts spinning around in the accretion disk in very high speeds? I doubt hawking radiation would do anywhere near that much
https://youtu.be/t-O-Qdh7VvQ
No, It is actually the light produced that we can actually use as a energy source, the limiting thing is, before completely loosing its kinetic energy to frictional heat, stuff falls into black hole, from where we can not get anymore energy back. If black hole is stationary, then its 6%, and if its spinning (and assuming the fastest spinning theoretically possible) - 42% (spinning black holes are smaller and have smaller radius of no-return
Ahhh alright I was thinking the black hole converting mass to energy for itself, not as if we were to try utilize it
we can't let the noble black hole keep all ye energy, ye shall liberate it
Whilst I get your point, their point is still valid in the sense that you just can't extract that energy from gasoline in a more efficient manner than just burning it. For practical purposes, gasoline truly is that much less energy dense.
For comparison:
Do you have a Lemmy client that supports mathematical functions?
Built-in LaTeX support would be so cool (and not that hard, Mathstodon has it)
With ollama, having smart local bots for your lemmy instance should be easy
Did you reply to the wrong comment?
In theory, yes. In practice, of those two only fission is currently viable.
If you can do nuclear fusion yea, it's more efficient. Cold fusion has been a sci Fi thing for a while; they mostly moved on to antimatter-matter annihilation, and ZPE(seems to be a favorite for sg1)