Question

The voltage of clouds is $4 \times 10^6 \,V$ with respect to ground. In a lightning strike lasting $100 \,ms$, a charge of $4 C$ is delivered to the ground. The power of lightning strike is

• A. $160 \, MW$
• B. $80 \,MW$
• C. $20 \,MW$
• D. $500 \, kW$

Answer 1

Answer: (A)

Work done in delivering $q$ coulomb of charge from clouds to ground,
$W =V q $
$ =4 \times 10^6 \times 4 $
$ =16 \times 10^6 J$
The power of lightning strike,
$P=\frac{W}{t}=\frac{16 \times 10^6}{0.1}=160 \times 10^6 W =160\, MW$