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A comment on EU experts to say nuclear power qualifies for green investment label: document. Parent comment

Re:EU experts to say nuclear power qualifies for green inves... by laurent92 on Saturday March 27, 2021 @03:34PM (#26604883)
Just for everyone to have a picture, uranium doesn’t take much room because it is quite heavy: 19.1g/cm3, denser than lead (11.3) but slightly less than gold (19.3) and plutonium (19.8).
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Re:EU experts to say nuclear power qualifies for green inves... by fastball on Saturday March 27, 2021 @03:47PM (#26605001)
The density of uranium is secondary to just how unbelievably energetic (per unit mass of fuel) fission is.
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Re:EU experts to say nuclear power qualifies for green inves... by loeg on Saturday March 27, 2021 @04:23PM (#26605292)
Energy density is the main reason you don't need much volume of uranium. Fission is just extremely energetic.

That c² factor in E = m c² is huge (9 * 10¹⁶).

It is really hard for humans to intuit about factors of ten to the power of 16 or 17.

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Re:EU experts to say nuclear power qualifies for green inves... by Jabbles on Saturday March 27, 2021 @04:32PM (#26605388)
You need to include the units, else that doesn't make much sense - many physicists use units such that c = 1.

In this case the units (for speed²) you want are m²/s² = J/kg

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Re:EU experts to say nuclear power qualifies for green inves... by loeg on Saturday March 27, 2021 @04:42PM (#26605477)
The fun thing is, the units are basically unimportant! A factor of 10^3 or two is peanuts on 10^17. Humans have just as terrible intuitions about 10^14 and 10^11 as they do about 10^17.
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Re:EU experts to say nuclear power qualifies for green inves... by exporectomy on Saturday March 27, 2021 @09:28PM (#26607231)
The error is 10^17, not 10^3. Units are important.
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