Two condensers, one of capacity $C$ and the other of capacity $\frac{C}{2}$ , are connected to a $V\, volt$ battery, as shown. The work done in charging fully both the condensers is
$\frac{1}{2}CV^2$
$2CV^2$
$\frac{1}{4}CV^2$
$\frac{3}{4}CV^2$
There is a square gaussian surface placed in $y-z$ plane. Its axis is along $x-$ axis and centre is at origin. Two identical charges, each $Q$, are placed at point $(a, 0, 0)$ and $(-a, 0, 0)$. Each side length of square is $2a$ then electric flux passing through the square is
Three charges $4q,\,Q$ and $q$ are in a straight line in the position of $0$, $l/2$ and $l$ respectively. The resultant force on $q$ will be zero, if $Q = $
Side length of equilateral triangle is $d. P$ is mid of side then potential at point $P, V_P$ is
A metallic shell has a point charge $'q'$ kept inside its cavity. Which one of the following diagrams correctly represents the electric field lines
Four identical capacitors are connected in series with a battery of $emf$ $10\,V$. The point $X$ is earthed, then the potential of point $A$ is.....$V$