Question

Energy equivalent of $2\, g$ of a substance is

• A. $18 \times 10^{13} mJ$
• B. $18 \times 10^{13} J$
• C. $9 \times 10^{13} mJ$
• D. $9 \times 10^{13} J$

Answer 1

Answer: (B)

Energy, $E=2 \times 10^{-3} \times\left(3 \times 10^{8}\right)^{2} J$
$E=2 \times 10^{-3} \times 9 \times 10^{16}=18 \times 10^{13} J$
Thus, if one gram of matter is converted to energy, there is a release of enormous amount of energy.