On Mon, Nov 25, 2013 at 3:56 PM, LizR <[email protected]> wrote: > I heard that hydrogen nuclei in the sun fuse after on average 5 billion > years of wandering around bumping into each other (I guess that's kind of > obvious - the Sun is due to "live" for about 10 billion years, so it must > use its fuel at a comparable rate). So the energy production per volume > would seem fairly low - one in 5 billion nuclei fuse per year, or one in > 150 x 10^15 per second. I guess density is around 10^23 per cubic meter > give or take an order of magnitude, so about a million atoms fuse per cubic > metre/second. If I read Wikipedia right, each one releases about 7 Mev so a > million release about 7 x 10^12 ev or around 10^-6 J/sec, which I believe > is one microwatt. > > Damn, I've slipped up somewhere, haven't I? Maybe someone with more of a > head for maths can do the calculation properly. > > > The density of the core is about 100 - 200 grams per cubic centimeter, which is far more than the gas at STP (it takes 22.4 liters to equal one mole of gas), so there would be ~50 times that volume in a cubic meter, and then the gas is probably thousands of times standard pressure, but I don't know the exact pressure necessary to get Hydrogen-helium plasma to that density, but I imagine this might account for the discrepancy in your calculation.
Jason > > On 25 November 2013 19:09, Jason Resch <[email protected]> wrote: > >> >> >> >> On Mon, Nov 25, 2013 at 12:57 AM, Chris de Morsella < >> [email protected]> wrote: >> >>> >>> >>> >>> >>> *From:* [email protected] [mailto: >>> [email protected]] *On Behalf Of *Jason Resch >>> *Sent:* Sunday, November 24, 2013 9:33 PM >>> *To:* Everything List >>> *Subject:* Re: Nuclear power >>> >>> >>> >>> >>> >>> >>> >>> On Sun, Nov 24, 2013 at 8:23 PM, Richard Ruquist <[email protected]> >>> wrote: >>> >>> Stars are essentially fusion bombs and stars can explode. >>> >>> >>> >>> I like the analogy that stars are essentially just giant compost heaps. >>> The levels of energy production in the core of the sun is quite low on a >>> per-volume basis: a few hundred watts per cubic meter. On the same order >>> as your own biological metabolism (and not much greater than that of a >>> compost heap). It is only by virtue of the huge volume of a star that it >>> produces large quantities of energy, but all the energy of a cubic meter of >>> stellar core would be just enough to run a TV or a computer. >>> >>> >>> >>> Very interesting; never considered it that way. Thanks for sharing. >>> >> >> Thanks, though I can't take credit for it, I found it on >> http://en.wikipedia.org/wiki/Solar_core#Energy_production which appears >> to be largely inspired from: >> http://www.abc.net.au/science/articles/2012/04/17/3478276.htm >> >> >>> So if a star is a compost heap, does that make a black hole the >>> swirling flush of a cosmic toilet? >>> >>> I know… pretty much, a non-sequitur, but such is life :) >>> >> >> :-) >> >> Jason >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
