Q. The work done in placing a charge of $8 \times 10^{- 18}C$ on a condenser of capacity 100$\mu$F is
A) $16 \times 10^{- 32}\ $J
B) 3.1$\times 10^{- 26}$J
C) $4 \times 10^{- 10}$J
D) $32 \times 10^{- 32}$J
Explanation
(d) $W = \frac{1}{2}\frac{q^{2}}{C}$
$\ \ \ \ \ \ = \frac{1}{2} \times \frac{\left( 8 \times 10^{- 18} \right)^{2}}{100 \times 10^{- 6}} = \frac{1}{2} \times \frac{64 \times 10^{- 36}}{100 \times 10^{- 6}} = 32 \times 10^{- 32}J$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.