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 condenser of capacity $50\,\mu F$ is charged to $10\;volts$. Its energy is equal to

Two Identical capacttors $\mathrm{C}_{1}$ and $\mathrm{C}_{2}$ of equal capacitance are connected as shown in the circult. Terminals $a$ and $b$ of the key $k$ are connected to charge capacitor $\mathrm{C}_{1}$ using battery of $emf \;V\; volt$. Now disconnecting $a$ and $b$ the terminals $b$ and $c$ are connected. Due to this, what will be the percentage loss of energy?.....$\%$

A $4 \;\mu\, F$ capacitor is charged by a $200\; V$ supply. It is then disconnected from the supply, and is connected to another uncharged $2 \;\mu\, F$ capacitor. How much electrostatic energy of the first capacitor is lost in the form of heat and electromagnetic radiation?

Two identical capacitors, have the same capacitance $C$. One of them is charged to potential ${V_1}$ and the other to ${V_2}$. The negative ends of the capacitors are connected together. When the positive ends are also connected, the decrease in energy of the combined system is

A parallel plate capacitor carries a charge $q$. The distance between the plates is doubled by application of a force. The work done by the force is