Question

The energy equivalent of $0.5g$ of a substance is _________.

Answer 1

Step 1 Given:

Mass of the substance is $m=0.5g=0.5\times {10}^{-3}Kg$;

Speed of the light is $c=3\times {10}^8\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s$}\right.$.

Step 2 Formula used:

The energy equivalent of the particular mass is $E=m{c}^2$.

Step 3 Calculating the energy equivalent:

$$\begin{gathered} E=0.5\times {10}^{-3}\times {\left(3\times {10}^8\right)}^2 \\ E=4.5\times {10}^{13}J \end{gathered}$$

Hence, The energy equivalent of $0.5g$ of a substance is $4.5\times {10}^{13}J$.