Question

A battery is used to charge a parallel plate capacitor till the potential difference between the plates becomes equal to the electromotive force of the battery. The ratio of the energy stored in the capacitor and the work done by the battery will be :

• A. $1$
• B. $2$
• C. $\frac{1}{4}$
• D. $\frac{1}{2}$

Answer 1

The correct option is D $\frac{1}{2}$

energy in capacitor = $\frac{1}{2}C{V}^2$
word done by battery =$VQ=VCV=C{V}^2$
therefore their ratio is $=\frac{1}{2}$