Question

The mass defect in a particular reaction is $0.4 \, \text{g}$. The amount of energy liberated is $n \times 10^7 \, \text{kWh}$, where $n =$ _____. (speed of light $= 3 \times 10^8 \, \text{m/s}$)

Answer 1

The energy liberated is given by:

$E = \Delta m c^2$

Substituting the values:

$E = 0.4 \times 10^{-3} \times (3 \times 10^8)^2$

$E = 3600 \times 10^7 \, \text{kWs}$

Converting to kWh:

$E = \frac{3600 \times 10^7 \, \text{kWh}}{3600} = 1 \times 10^7 \, \text{kWh}$