
$\therefore Q_{1}=C V ;$
$Q_{2} =\frac{C}{2} V $
$\text { Also }, Q =Q_{1}+Q_{2}$
$ = CV+\frac{C}{2} V=\frac{3}{2} C V$
Work done in charging fully both the condensors is given by
$W=\frac{1}{2} Q V=\frac{1}{2} \times\left(\frac{3}{2}\, C V\right) V=\frac{3}{4} \,C V^{2}$



$1.$ A sphere $2.$ Cylindrical
$3.$ Pear $4.$ Lightning conductor
are mounted on insulating stands and charged. The one which is best suited to retain the charges for a longer time is
