*Boo

(But having a book instead is always nice.)

which is bigger? TREE(3) vs

((...(1 room of stacked papers ) room of paper) room of paper)...)) room of paper

The number of brackets in above expression is, eh, ok, you got the idea.

/s

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.

How much more energy would you get if you fused uranium?

It's disappointing that natural selection didn't figure out fusion.

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:

• Chemical combustion of uranium: ~4.7 MJ/kg
• Nuclear fission of uranium-235: ~83.14 TJ/kg (or $ 83.14 \times 10^6 , \text{MJ/kg} $)

and all would generate the same if thrown to something capable of lossless e=mc^2 conversion (maybe a black hole)

In theory, yes. In practice, of those two only fission is currently viable.

I think that's technically true regardless.

I was thinking the same thing. It's unfair compare chemical energy to nuclear energy. Coal still kind of sucks, but the hydrogen in the others could definitely be used in fusion...