illiad wrote:
hey, I dont know properly, but even an Atom bomb does not release the energy 'immediately'(it needs to build up a chain reaction ), and NOT even 'efficiently! ...
Correct. The chain reaction in an atomic bomb is typically measured in "shakes" (1 shake = 10 nanoseconds = .01 microsecond). Each fission step in the reaction (fissile nucleus captures a neutron, goes unstable, splits, and shoots out several other neutrons) takes approximately 1 shake. The total chain reaction for an A-bomb takes somewhere on the order of 50-100 shakes.
So, the actual fission reaction (the matter-to-energy stage) is over in about a millionth of a second. Due to the geometric build-up in the number of atoms which are splitting in each step, most of the energy release comes at the end, during the last few doublings. By the time the fission cascade ends, the very first gamma rays emitted from the core are only a few hundred yards down the block, and the strongest part of the energy pulse hasn't gone even that far. I was more than a bit surprised to learn it was that fast!
The explosion that we see, is all the result of energy that's already been released (very suddenly) being propagated outwards, a lot more slowly.
'Fatman' the first Atomic bomb, was 3 metres long, and weighed 4,670 kg - It contained 6.2 kg of Plutonium... giving a blast of 21KT ... how small is a penny????
Also correct. Simple FatMan-type fission weapons aren't very efficient. 6200 grams of plutonium, only about 17% of it actually underwent fission, and the actual amount of mass lost during the fission was only around 600 milligrams - so it was about 0.1% efficient at turning its fissile mass into energy. Fat Man lost *less* than a penny's worth of mass when it went kaboom... all the rest turned into plasma and gas and particles, and ended up as fallout.
Modern "fusion-boosted" fission weapons are much more efficient - much higher yields for a given amount of plutonium. Most modern "H-bombs" generate only a small amount of energy from the fusion of hydrogen; the fusing hydrogen (and lithium) releases a big blast of neutrons, which trigger additional fission in the plutonium and/or uranium.
Total conversion (matter/antimatter annihilation) can be anywhere up to 100% efficient, depending on how thoroughly you can mix the materials (and, as Scotty said in great anguish, "Ye canna' mix matter and anti-matter cold!". Not and survive, at least, in the Trek universe).
And what of Lazarus? Did he ever marry Naomi?
