dmjalund Posted June 30, 2018 Report Share Posted June 30, 2018 shall we make it so? Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted June 30, 2018 Report Share Posted June 30, 2018 Where? Quote Link to comment Share on other sites More sharing options...
Bazza Posted June 30, 2018 Report Share Posted June 30, 2018 No? i mean no Quote Link to comment Share on other sites More sharing options...
Old Man Posted June 30, 2018 Report Share Posted June 30, 2018 What is a question thread? Quote Link to comment Share on other sites More sharing options...
Pariah Posted June 30, 2018 Report Share Posted June 30, 2018 I'll take "Redundancy" for $400, Alex. Quote Link to comment Share on other sites More sharing options...
Starlord Posted June 30, 2018 Report Share Posted June 30, 2018 Are there enough questions in the world to fill two threads? Quote Link to comment Share on other sites More sharing options...
Old Man Posted June 30, 2018 Report Share Posted June 30, 2018 Are there enough answers in the world to fill a shot glass? Quote Link to comment Share on other sites More sharing options...
Ternaugh Posted June 30, 2018 Report Share Posted June 30, 2018 Quote Link to comment Share on other sites More sharing options...
mattingly Posted July 1, 2018 Report Share Posted July 1, 2018 Do you want it to be? Quote Link to comment Share on other sites More sharing options...
Ternaugh Posted July 1, 2018 Report Share Posted July 1, 2018 Would you like to know more? Quote Link to comment Share on other sites More sharing options...
Pariah Posted July 1, 2018 Report Share Posted July 1, 2018 No. This is not the question thread. We have one of those already. A second would be superfluous. Move along. Nothing to see here. Bazza 1 Quote Link to comment Share on other sites More sharing options...
dmjalund Posted July 1, 2018 Author Report Share Posted July 1, 2018 1 hour ago, Pariah said: No. This is not the question thread. We have one of those already. A second would be superfluous. Move along. Nothing to see here. Can you point me to the questions thread then? Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted July 1, 2018 Report Share Posted July 1, 2018 Over there. Quote Link to comment Share on other sites More sharing options...
dmjalund Posted July 1, 2018 Author Report Share Posted July 1, 2018 4 hours ago, L. Marcus said: Over there. over where? Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted July 1, 2018 Report Share Posted July 1, 2018 *points* Quote Link to comment Share on other sites More sharing options...
Starlord Posted July 1, 2018 Report Share Posted July 1, 2018 Ow! Be careful. Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted July 1, 2018 Report Share Posted July 1, 2018 Never! Quote Link to comment Share on other sites More sharing options...
Cancer Posted July 2, 2018 Report Share Posted July 2, 2018 1. Compute the heat from accretion of the early Earth. (This is equivalent to computing the gravitational potential energy of a uniform sphere wi Earth's mass and radius.) 2. Compute the heat release from Earth's differentiation. (This is, very roughly, the difference between the answer to part 1 and a simple model of the differentiated Earth: a unform core, a sphere of radius 3200 km and density 11 tons per cubic meter, a crust of uniform density 3.5 tons/m3 and a thickness of 50 km, with outer radius = current Earth radius, and the space between those occupied by a mantle of density 5 T/m3.) 3. Compute the nuclear energy release in Earth's interior over its history. Taking the initial bulk composition of Earth found here, look up the half-lives of K-40, U-238, and U-235, and work out how much mass-energy is released assuming each nucleus that undergoes any decay is in the final daughter product; deduct the mass-energy in released alpha particles (if any). Compute the total energy release from each nucleus, and sum them to get the nuclear energy release. 4. Compare the values in parts 1-3, and the contributions by the three main unstable nuclei. Quote Link to comment Share on other sites More sharing options...
Starlord Posted July 2, 2018 Report Share Posted July 2, 2018 Do I have to do everything for you? Quote Link to comment Share on other sites More sharing options...
Pariah Posted July 2, 2018 Report Share Posted July 2, 2018 9 hours ago, Cancer said: 1. Compute the heat from accretion of the early Earth. (This is equivalent to computing the gravitational potential energy of a uniform sphere wi Earth's mass and radius.) 2. Compute the heat release from Earth's differentiation. (This is, very roughly, the difference between the answer to part 1 and a simple model of the differentiated Earth: a unform core, a sphere of radius 3200 km and density 11 tons per cubic meter, a crust of uniform density 3.5 tons/m3 and a thickness of 50 km, with outer radius = current Earth radius, and the space between those occupied by a mantle of density 5 T/m3.) 3. Compute the nuclear energy release in Earth's interior over its history. Taking the initial bulk composition of Earth found here, look up the half-lives of K-40, U-238, and U-235, and work out how much mass-energy is released assuming each nucleus that undergoes any decay is in the final daughter product; deduct the mass-energy in released alpha particles (if any). Compute the total energy release from each nucleus, and sum them to get the nuclear energy release. 4. Compare the values in parts 1-3, and the contributions by the three main unstable nuclei. I'm going to show this to my Geology and Astronomy professors this week. I'll let you know what they say. Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted July 2, 2018 Report Share Posted July 2, 2018 Answers to questions one through three: a whole heap o' joules! Quote Link to comment Share on other sites More sharing options...
Pariah Posted July 2, 2018 Report Share Posted July 2, 2018 He probably wants the answers in eV, though. Quote Link to comment Share on other sites More sharing options...
Starlord Posted July 2, 2018 Report Share Posted July 2, 2018 No problem 1. New Years eV 2. Christmas eV 3. All-hallows eV Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted July 2, 2018 Report Share Posted July 2, 2018 ... Is the electron-volt an SI unit? Quote Link to comment Share on other sites More sharing options...
Cancer Posted July 2, 2018 Report Share Posted July 2, 2018 3 hours ago, Pariah said: I'm going to show this to my Geology and Astronomy professors this week. I'll let you know what they say. Intended level: upper-division undergraduate science major. Quote Link to comment Share on other sites More sharing options...
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