Question

The mass defect in a particular nuclear reaction is $0.3grams$. The amount of energy liberated in kilowatt hour is: (Velocity of light = $3\times {10}^{8}m/s$)

• A. $1.5\times {10}^6$
• B. $2.5\times {10}^6$
• C. $3\times {10}^6$
• D. $7.5\times {10}^6$

Answer 1

Answer: (D)

$7.5\times {10}^6$

$E=\left(△m\right)c^2$

$\Rightarrow E=\frac{0.3}{1000}\times {(3\times {10}^8)}^2=2.7\times {10}^{13}J$$=\frac{2.7\times {10}^{13}}{3.6\times {10}^6}=7.5\times {10}^{6}kWh$