waross said:18,590 lbs x 12,000 ft depth = 223,080,000 ft lbs of energy in the collapse.
It's close. The volume is slightly less though. I have 6.2m3.
So the energy in SI is 3600m * 6.2m3 * 1000kg * 9.8 = 218736000 J (161333530 ft lbs)
1 gram of TNT is 4184 J, i.e. the energy is 218736000/4184 = 52279 gram of TNT. That's a figure being bandied about in the first thread. 50kg of TNT
IRStuff said:Even if you fixed the units, you're calculating gravitational potential energy, which is not relevant for this problem
The energy is the gravitational potential of the volume of displaced water