Find capacitance across $AB$
$\frac{C}{3}$
$3C$
$C$
None of these
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
Four charges are placed at the circumference of a dial clock as shown in figure. If the clock has only hour hand, then the resultant force on a charge $q_0$ placed at the centre, points in the direction which shows the time as:
A charge $2\,\mu C$ is taken from infinity to a point in an electric field, without changing its velocity. If work done against forces is $20\,\mu J$ then potential at that point will be.....$V$
Charge $q$ is uniformly distributed over a thin half ring of radius $R$. The electric field at the centre of the ring is
A charge $q$ is placed at the centre of the line joining two equal charges $Q$. The system of the three charges will be in equilibrium, if $q$ is equal to