The atomic bomb that was dropped on Nagasaki in 1945 killed 140,000 people, helping to end World War II on the next day. It released energy equivalent to that of 20,000 tons of TNT explosive. How much mass was converted to energy when this took place? (1000 tons of TNT = 4.3 × 10¹² J) Incidentally, modern H-bombs have energy yields 1000 times as much! A)1 g B)10 g C)100 g D)1 kg E)10 kg

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Quizplus · Accepted Answer

The energy released by the bomb is 20,000 tons of TNT, which is 20,000 x 4.3 × 10^12 J = 8.6 × 10^16 J. Using E=mc^2, where c is the speed of light (3 × 10^8 m/s), the mass converted to energy is m = E/c^2 = 8.6 × 10^16 J / (9 × 10^16 m^2/s^2) = 0.955 g, approximately 1 g.

The Atomic Bomb That Was Dropped on Nagasaki in 1945