5 ms·

We did this calculation in a course I took in college. I've completely forgotten how it worked.

• Declanomous 10y ago
  Assuming the paper shifted perfectly laterally, I assume you'd just be measuring the difference in the volume of half a sphere ten miles in radius, and a sphere ten miles and 2.5 meters in radius. I think you could use the ideal gas law at that point to figure out the energy. I'm just guessing though.
  • iaw 10y ago
    I think you're right. Ideal gas law wouldn't apply to the plasma sphere but knowing shockwave strength at some distance you can figure out how much energy was transferred to the atmosphere.
    • adrianratnapala 10y ago
      I agree the calculation probably worked by measuring the kinectic energy of that half-shell by measuring its velocity*thickness directly using pieces of paper. But I wouldn't count the ideal gas law out (see http://physics.stackexchange.com/questions/43696/will-ideal-gas-law-apply-to-plasma http://physics.stackexchange.com/questions/43696/will-ideal-...). My guess is that the huge temperatures involved will work in favour of an ideal-gas approximation. Perhaps the more important thing is that things are happening on very short time-scales, far enough from equilibrium and temperature might not even be well defined.
      • Declanomous 10y ago
        That probably would work better. I tried doing the math and ended up with some really weird answers. Definitely not 10 kt.