Deutsch English Français Italiano |
<7385bfc7c2c172eb9c645aa1d675abb4@www.novabbs.com> View for Bookmarking (what is this?) Look up another Usenet article |
Path: ...!eternal-september.org!feeder3.eternal-september.org!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: tomyee3@gmail.com (ProkaryoticCaspaseHomolog) Newsgroups: sci.physics.relativity Subject: Re: Want to prove =?UTF-8?B?RT1tY8KyPyBVbml2ZXJzaXR5IGxhYnMgc2hvdWxkIHRy?= =?UTF-8?B?eSB0aGlzIQ==?= Date: Tue, 26 Nov 2024 20:50:43 +0000 Organization: novaBBS Message-ID: <7385bfc7c2c172eb9c645aa1d675abb4@www.novabbs.com> References: <b00a0cb305a96b0e83d493ad2d2e03e8@www.novabbs.com> <ebcad35958736e6602cf803fddfdb0fd@www.novabbs.com> <141e19a1c6acd54116739058391ca9f8@www.novabbs.com> <a4f98fa5d026bfbf5127fcbc6a585772@www.novabbs.com> <aGN%O.47052$2d0b.43303@fx09.ams4> <45ed9424edce8c13db24c1dbb8752c26@www.novabbs.com> <c8df6716ae871b79524720426a3f229a@www.novabbs.com> <7adfc9e5c6884729def0c6a0097c9f37@www.novabbs.com> <humdnTd1BNWduN36nZ2dnZfqn_idnZ2d@giganews.com> <092fa494db9895ba52cfac350be5e744@www.novabbs.com> <afe961104287110aab310b0cc3b5f8ef@www.novabbs.com> <98654d26cc4f5fd326f071ea7d4317b8@www.novabbs.com> <6292a6508a7a1b7e2f7d13951685410d@www.novabbs.com> <7387e2f099b81abacc7cf1184a11db86@www.novabbs.com> <c25f832f113e2f2e620db970e654daaf@www.novabbs.com> <1c8ddce1b3c5cc1caa998058c5cb0abe@www.novabbs.com> <014401c969346dfb15470705c326f119@www.novabbs.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Info: i2pn2.org; logging-data="69752"; mail-complaints-to="usenet@i2pn2.org"; posting-account="Ooch2ht+q3xfrepY75FKkEEx2SPWDQTvfft66HacveI"; User-Agent: Rocksolid Light X-Spam-Checker-Version: SpamAssassin 4.0.0 X-Rslight-Site: $2y$10$zns0vVWRuMIgoSmQvZyrwukHYQhsZ/cgtIZ4Tpf./Vp/xWz5pu0vC X-Rslight-Posting-User: 504a4e36a1e6a0679da537f565a179f60d7acbd8 Bytes: 4564 Lines: 81 On Tue, 26 Nov 2024 18:29:11 +0000, rhertz wrote: > On Tue, 26 Nov 2024 8:27:15 +0000, ProkaryoticCaspaseHomolog wrote: > >> On Mon, 25 Nov 2024 21:54:34 +0000, rhertz wrote: >> >>> This means that half of the accumulated 955 Joules remain within the >>> cavity. >> >> 477.5 Joules of energy in a volume of 5.236e-4 m^3 implies a energy >> energy density u (assumed to be black body) within the shell of >> 9.12e4 J/m^3 >> >> u = 4 σ T^4/c >> 9.12e4 = 4 * 5.67e^-8 T^4/3.0e^8 >> T^4 = 120,634,920,634,920,634,920 >> T = 1.05e5 K temperature of the black body radiation >> >> Your numbers don't make sense. > > Your entire post don't make sense. > > 1) Your u value is wrong by 10 times. It should be u = 9.12e5 J/m^3. Yes, I dropped a digit. So things are even WORSE for you. The effective black body temperature corresponding to that radiation density is 1.86e5 K > 2) You applied incorrectly how the radiation is spread within the > cavity. > > > P = uc/4 is the radiative FLUX of energy being radiated in 3D, traveling > at the speed of light. The factor 4 is due to the integration of energy > moving omnidirectionally and being radiated toward infinity, which IS > NOT THE CASE HERE, INSIDE THE CAVITY. > > The 477.5 Joules ARE CONFINED in the cavity, and the radiation keeps > bouncing within its volume. > > At any case, it would give a radiative flux P = 6.84E+13 J m^-2/sec. Read that out loud and ask yourself if that is reasonable. 68.4 trillion watts per square meter. From a 5 watts of input power. > When you modify the Stefan-Boltzmann law by writing u = 4 σ T^4/c, > you're assuming that the energy propagates spherically without > attenuation. At any case, T = 186,364 K, a value that HAS NO MEANING > AT ALL. It has a very definite meaning. See the discussion in "Energy density" https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law#Energy_density > 3) Using correctly the influence of energy within the cavity filled with > air (behaving as an ideal gas), you have: > > E = 3/2 nRT > > n = PV/RT , moles of air in the volume > R = 8.3145 kJ/kmol K (ideal gas) > R = 0.287 kJ/kg K (air) > > > ΔT = 2E/(3 PV) = 6 K , the increase above room temperature. What type of numerology are you using? Where did you get a value of E to plug into that? Check your units. PV has dimensions of energy, so 2E(3 PV) is a dimensionless number. > As you can see, this is a much more reasonable value. > > What would you expect if you use a 5 W incandescent lamp heating the > cavity? > > Only 6"C increase in the inner temperature after a couple of minutes. Yet you claim that that 5 watt incandescent lamp will raise the temperature to 707 K.