On August 10, 1972, a big meteorite skipped across the atmosphere above western United States and western Canada, much similar to a stone skipped across water. The accompanying fireball was so bright that it could be seen in the daytime sky and was brighter than the usual meteorite trail. The mass of meteorite was about 4 x106 kg. Its speed was about 15 km/s. Had it entered the atmosphere vertically, it would have strike the surface of Earth with about the similar speed.
(i) Compute the meteorite's loss of kinetic energy (in joules) which would have been related with the vertical impact.
(ii) Represent the energy as a multiple of the explosive energy of 1 megaton of TNT that is 4.2 x 1015 J.
(iii) The energy related with the atomic bomb explosion over Hiroshima was equivalent to 13 kilotons of TNT. To how many Hiroshima bombs would the meteorite impact have been equal?