Mass–energy equivalence
How much energy is released when 1 g of mass is converted completely to energy (c = 3 × 10⁸ m/s)?
Answer C: explanation for every choice
A
This uses mc instead of mc².
B
This converts 1 g to 10⁻⁶ kg instead of 10⁻³ kg.
C
Correct. E = mc² = (10⁻³ kg)(9 × 10¹⁶ m²/s²) = 9 × 10¹³ J.
D
This uses 1 kg instead of 1 g.
TakeawayE = mc², with mass in kilograms.
Equation usedMass–energy equivalence
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