On Mon, Nov 25, 2013 at 3:56 PM, LizR <lizj...@gmail.com> 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 <jasonre...@gmail.com> wrote: > >> >> >> >> On Mon, Nov 25, 2013 at 12:57 AM, Chris de Morsella < >> cdemorse...@yahoo.com> wrote: >> >>> >>> >>> >>> >>> *From:* everything-list@googlegroups.com [mailto: >>> everything-list@googlegroups.com] *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 <yann...@gmail.com> >>> 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 everything-list+unsubscr...@googlegroups.com. >> To post to this group, send email to everything-list@googlegroups.com. >> 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 everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > 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 everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
