Word for the Day
The A-bomb, or atomic bomb, first tested and used in 1945, operates on the principle of nuclear fission—the splitting of the nuclei of uranium or plutonium atoms—which suddenly releases an incredible amount of explosive energy. The H-bomb (hydrogen bomb), first tested in 1952, is a fusion rather than fission device, joining the nuclei of hydrogen atoms together in an uncontrolled nuclear reaction. The hydrogen bomb releases about 1,000 times more energy than an atomic bomb.