Half of the space between parallel plate capacitor is filled with a medium of dielectric constant $K$ parallel to the plates . If initially the capacity is $C$, then the new capacity will be
$2KC/(1+K)$
$C\, (K+1)/2$
$CK/(1+K)$
$KC$
Two parallel metal plates having charges $+ Q$ and $-Q$ face each other at a certain distance between them. If the plates are now dipped in kerosene oil tank, the electric field between the plates will
A capacitor of capacitance $C_0$ is charged to a potential $V_0$ and is connected with another capacitor of capacitance $C$ as shown. After closing the switch $S$, the common potential across the two capacitors becomes $V$. The capacitance $C$ is given by
In the circuit shown in the figure, the potential difference across the $4.5\,\,\mu F$ capacitor is.......$volts$
The force on a charge situated on the axis of a dipole is $F$. If the charge is shifted to double the distance, the new force will be
Four charges equal to $-Q$ are placed at the four corners of a square and a charge $q$ is at its centre. If the system is in equilibrium, the value of $q$ is