If 7.84 × 107 J of energy is released from a fusion reaction, what amount of mass in kilograms would be lost? Recall that c = 3 × 108 m/s.
This requires use of that well known equation E = mc2
Rearrange to get m = E/c2
m=7.84*107/(3*108)2 kg = (7.84/9)*10-9 kg. ≈ 8.7*10-10 kg
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