A capacitor of capacity $C$ has charge $Q$ and stored energy is $W$. If the charge is increased to $2Q$, the stored energy will be
A$2W$
B$W/2$
C$4W$
D$W/4$
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C$4W$
c (c) $W = \frac{{{Q^2}}}{{2C}}$ $==>$ $W' = 4W$
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