Express 16 mg mass into equivalent energy in eV

The correct answer is Option (1) → \( 9\times10^{30}\,\mathrm{eV} \)

Einstein's mass-energy relation \( E = mc^{2} \) gives the energy equivalent of a mass, which is then converted to electron-volts with \( 1\,\mathrm{eV} = 1.6\times10^{-19}\,\mathrm{J} \).

    \( \displaystyle m = 16\,\mathrm{mg} = 16\times10^{-6}\,\mathrm{kg} = 1.6\times10^{-5}\,\mathrm{kg} \)

    \( \displaystyle E = mc^{2} = 1.6\times10^{-5} \times (3\times10^{8})^{2} = 1.44\times10^{12}\,\mathrm{J} \)

    \( \displaystyle E = \frac{1.44\times10^{12}}{1.6\times10^{-19}}\,\mathrm{eV} = 9\times10^{30}\,\mathrm{eV} \)