A sphere of radius $R$ and charge $Q$ is placed inside an imaginary sphere of radius $2R$ whose centre coincides with the given sphere. The flux related to imaginary sphere is
$\frac{Q}{{ \in _0}}$
$\frac{Q}{{2 \in _0}}$
$\frac{4Q}{{ \in _0}}$
$\frac{2Q}{{ \in _0}}$
Five capacitors are connected to a $DC$ potential of $100\,V$ as shown in the adjoining figure. Find charge in $10\,μF$ capacitor......$μF$
A particle of mass $m$ and charge $q$ is placed at rest in a uniform electric field $E$ and then released. The $KE$ attained by the particle after moving a distance $y$ is
In steady state heat conduction, the equations that determine the heat current $j ( r )$ [heat flowing per unit time per unit area] and temperature $T( r )$ in space are exactly the same as those governing the electric field $E ( r )$ and electrostatic potential $V( r )$ with the equivalence given in the table below.
Heat flow | Electrostatics |
$T( r )$ | $V( r )$ |
$j ( r )$ | $E ( r )$ |
We exploit this equivalence to predict the rate $Q$ of total heat flowing by conduction from the surfaces of spheres of varying radii, all maintained at the same temperature. If $\dot{Q} \propto R^{n}$, where $R$ is the radius, then the value of $n$ is
Two condensers $C_1$ and $C_2$ in a circuit are joined as shown in figure. The potential of point $A$ is $V_1$ and that of $B$ is $V_2$. The potential of point $D$ will be
The conducting spherical shells shown in the figure are connected by a conductor. The capacitance of the system is