Question

In figure, charge on the capacitor is plotted against potential difference across the capacitor. The capacitance and energy stored in the capacitor are respectively.

• A. $12\, \mu F , 1200\, \mu J$
• B. $12\, \mu F , 600 \,\mu J$
• C. $24\, \mu F , 600 \,\mu J$
• D. $24\, \mu F , 1200 \,\mu J$

Answer 1

Answer: (B)

$q = CV $
$ C =\frac{ q }{ V }=\frac{120 \times 10^{-6}}{10}=12 \times 10^{-6} F $
$ C =12 \,\mu F $
$ U =\frac{1}{2} CV ^{2}$
$=\frac{1}{2} \times 12 \times 10^{-6} \times 10 \times 10 $
$ U =600 \times 10^{-6} J $
$ U =600 \,\mu J $