Calculate the work done in taking a charge $-2 \times 10^{-9} \,C$ from $A$ to $B$ via $C$ is ......... (in diagram)

If potential at centre of uniformaly charged ring is $V_0$ then electric field at its centre will be (assume radius $=R$ )

A parallel plate capacitor has plates with area $A$ and separation $d$ . A battery charges the plates to a potential difference $V_0$. The battery is then disconnected and a dielectric slab of thickness $d $ is introduced. The ratio of energy stored in the capacitor before and after the slab is introduced is

As shown in the fig. charges $+\,q$ and $-\,q$ are placed at the vertices $B$ and $C$ of an isosceles triangle. The potential at the vertex $A$ is

A wheel having mass $m$ has charges $+q$ and $-q$ on diametrically opposite points. It  remains in equilibrium on a rough inclined plane in the presence of uniform horizontal  electric field $E =$

The electric potential $(V)$ as a function of distance $(x)$ [in meters] is given by $V = (5x^2 + 10 x -9)\, Volt$. The value of electric field at $x = 1\, m$ would be......$Volt/m$