The $V-Q$ graph is shown below. What does the area of $\triangle OAB$ represent in this graph?

$A$ capacitor of capacitance $C$ has stored energy $W$ and charge $Q$. If the charge is increased to $2Q$,what will be the new stored energy?

$A$ capacitor having a capacity of $2.0 \; \mu F$ is charged to $200 \; V$ and then the plates of the capacitor are connected to a resistance wire. The heat produced in joules will be:

$A$ battery is used to charge a parallel plate capacitor until the potential difference between the plates becomes equal to the e.m.f. of the battery. The ratio of the energy stored in the capacitor to the work done by the battery will be

$A$ parallel plate capacitor has plate area $A$ and separation between plates is $d$. It is charged to a potential difference of $V_0$ volt. The charging battery is then disconnected and plates are pulled apart to three times the initial distance. The work done to increase the distance between the plates is $(\varepsilon_0 = \text{permittivity of free space})$

The charge $q$ on a capacitor varies with voltage $V$ as shown in the figure. The area of the triangle $AOB$ is proportional to