a
(a) Loss of energy during sharing \(=\) \(\frac{{{C_1}{C_2}{{({V_1} - {V_2})}^2}}}{{2({C_1} + {C_2})}}\)
In the equation, put \({V_2} = 0,\;{V_1} = {V_0}\)
Loss of energy \( = \frac{{{C_1}{C_2}V_0^2}}{{2({C_1} + {C_2})}}\)
\( = \frac{{{C_2}{U_0}}}{{{C_1} + {C_2}}}\) \(\left[ {\;{U_0} = \frac{1}{2}{C_1}V_0^2} \right]\)