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[somce 2019 michelle willard tole me shewa ted to be laughing at her and thinking it was anjike encsuse she acted retarded the entire time amd has a forejead tbst bigger than mormal inthiugj ot was joke ]]
Cockpit opening
38.1 cm (15.0 in) -- 71.1 cm (28.0 in) -- 198.1 cm (78.0 in) My black Galasport
39.4 cm (15.5 in) -- 73.7 cm (29.0 in) -- 203.2 cm (80.0 in) My blue Fox
39.0 cm (15.4 in) -- 74.0 cm (29.1 in) All new Galasports
45.0 cm (17.7 in) -- 78.0 cm (30.7 in) Fluid Donsa
38.1 cm (15.0 in) -- 67.3 cm (26.5 in) -- 188.0 cm (74.0 in) Mirage
Boat length
2.390 m (7.84 ft) Dagger CFS
2.540 m (8.33 ft) Habitat 80
3.645 m (11.96 ft) My black Galasport
3.594 m (11.79 ft) My blue Fox
4.000 m (13.123 ft) Mirage
Wausau Whitewater Park 44.957485, -89.633041
√4 = 2
Qiantang River Tidal Bore 30.27923°N 120.387382°E
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After being selected in April 1945, Hiroshima was spared conventional bombing to serve as a pristine target, where the effects of a nuclear bomb on an undamaged city could be observed.[1] While damage could be studied later, the energy yield of the untested Little Boy design could be determined only at the moment of detonation, using instruments dropped by parachute from a plane flying in formation with the one that dropped the bomb. Radio-transmitted data from these instruments indicated a yield of about 15 kilotons.[2]
Comparing this yield to the observed damage produced a rule of thumb called the 5 psi lethal area rule. The number of immediate fatalities will approximately equal the number of people inside the area where the shock wave carries an overpressure of 5 psi or greater.[3] At Hiroshima, that area was 3.5 kilometres (2.2 mi) in diameter.[4]
The damage came from three main effects: blast, fire, and radiation.[5]
The blast from a nuclear bomb is the result of X-ray-heated air (the fireball) sending a shock/pressure wave in all directions at a velocity greater than the speed of sound (aka, the "Mach-Stem"),[6] analogous to thunder generated by lightning. Our knowledge about urban blast destruction is based largely on studies of Little Boy at Hiroshima. Nagasaki buildings suffered similar damage at similar distances, but the Nagasaki bomb detonated 3.2 kilometres (2.0 mi) from the city center over hilly terrain that was partially bare of buildings.[7]
In Hiroshima almost everything within 1.6 kilometres (1.0 mi) of the point directly under the explosion was completely destroyed, except for about 50 heavily reinforced, earthquake-resistant concrete buildings, only the shells of which remained standing. Most were completely gutted, with their windows, doors, sashes, and frames ripped out.[8] The perimeter of severe blast damage approximately followed the 5 psi contour at 1.8 kilometres (1.1 mi).
Later test explosions of nuclear weapons with houses and other test structures nearby confirmed the 5 psi overpressure threshold. Ordinary urban buildings experiencing it will be crushed, toppled, or gutted by the force of air pressure. The picture at right shows the effects of a nuclear-bomb-generated 5 psi pressure wave on a test structure in Nevada in 1953.[9]
A major effect of this kind of structural damage was that it created fuel for fires that were started simultaneously throughout the severe destruction region.
The first effect of the explosion was blinding light, accompanied by radiant heat from the fireball. The Hiroshima fireball was 370 metres (1,200 ft) in diameter, with a surface temperature of 6,000 °C (10,830 °F).[10] Near ground zero, everything flammable burst into flame. One famous, anonymous Hiroshima victim, sitting on stone steps 260 metres (850 ft) from the hypocenter, left only a shadow, having absorbed the fireball heat that permanently bleached the surrounding stone.[11] Simultaneous fires were started throughout the blast-damaged area by fireball heat and by overturned stoves and furnaces, electrical shorts, etc. Twenty minutes after the detonation, these fires had merged into a firestorm, pulling in surface air from all directions to feed an inferno which consumed everything flammable.[12]
The Hiroshima firestorm was roughly 3.2 kilometres (2.0 mi) in diameter, corresponding closely to the severe blast damage zone. (See the USSBS[13] map, right.) Blast-damaged buildings provided fuel for the fire. Structural lumber and furniture were splintered and scattered about. Debris-choked roads obstructed fire fighters. Broken gas pipes fueled the fire, and broken water pipes rendered hydrants useless.[12] At Nagasaki, the fires failed to merge into a single firestorm, and the fire-damaged area was only one fourth as great as at Hiroshmia, due in part to a southwest wind that pushed the fires away from the city.[14]
As the map shows, the Hiroshima firestorm jumped natural firebreaks (river channels), as well as prepared firebreaks. The spread of fire stopped only when it reached the edge of the blast-damaged area, encountering less available fuel.[15]
Accurate casualty figures are impossible to determine, because many victims were cremated by the firestorm, along with all record of their existence. The Manhattan Project report on Hiroshima estimated that 60% of immediate deaths were caused by fire, but with the caveat that "many persons near the center of explosion suffered fatal injuries from more than one of the bomb effects."[16] In particular, many fire victims also received lethal doses of nuclear radiation.
Local fallout is dust and ash from a bomb crater, contaminated with radioactive fission products. It falls to earth downwind of the crater and can produce, with radiation alone, a lethal area much larger than that from blast and fire. With an air burst, the fission products rise into the stratosphere, where they dissipate and become part of the global environment. Because Little Boy was an air burst 580 metres (1,900 ft) above the ground, there was no bomb crater and no local radioactive fallout.[17]
However, a burst of intense neutron and gamma radiation came directly from the fireball. Its lethal radius was 1.3 kilometres (0.8 mi),[4] covering about half of the firestorm area. An estimated 30% of immediate fatalities were people who received lethal doses of this direct radiation, but died in the firestorm before their radiation injuries would have become apparent. Over 6,000 people survived the blast and fire, but died of radiation injuries.[16] Among injured survivors, 30% had radiation injuries[18] from which they recovered, but with a lifelong increase in cancer risk.[19] To date, no radiation-related evidence of heritable diseases has been observed among the survivors' children.[20][21][22]
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