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0 pointsloeg5y ago0 comments

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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Jabbles5y ago

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

loegOP5y ago

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.

exporectomy5y ago

The error is 10^17, not 10^3. Units are important.

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