Charge of $2Q$ and $-Q$ are placed on two plates of a parallel plate capacitor if capacitance of capacitor is $C$ find potential difference between the plates

In the figure a potential of $+1200\, V$ is given to point $A$ and point $B$ is earthed, what is the potential at the point $P$ ?......$V$

The four capacitors, each of $25\,\mu F$ are connected as shown in Fig. The $dc$ voltmeter reads $200\,V$. The charge on each plate of capacitor is

The electric field $\vec E$  between two points is constant in both magnitude and direction. Consider a path of length d at an angle $\theta  = 60^o$  with respect to field lines shown in figure. The potential difference between points  $1$ and $2$  is

A negative charged particle is released from rest in a uniform electric field. The electric potential energy of charge

Four metallic plates, each with a surface area of one side $A$, are placed at a distance $d$ from each other. The plates are connected as shown in the figure. The capacitance of  the system between $a$ and $b$ is