For a hollow spherical shell of radius $R$ carrying a charge $q$,how does the electric potential $(V)$ change with respect to the distance $(s)$ from the centre?

The charge on each capacitor when a voltage source of $15 \ V$ is connected in the circuit as shown,is (in $\mu C$)

$A$ parallel plate capacitor,after being charged,is kept connected to a battery,and the plates are pulled apart with the help of insulating handles. Which of the following quantities will decrease?

$A$ fully charged capacitor of capacity $C$ is discharged through a small resistance wire embedded in a solid block of specific heat $s$ and mass $m$ under thermally isolated conditions. If the temperature of the block is raised by $\Delta T$,the initial potential difference across the capacitor is

Three concentric conducting spherical shells have radii $r, 2r$ and $3r$ and $Q_1, Q_2$ and $Q_3$ are final charges respectively. The innermost and outermost shells are earthed as shown in the figure. Choose the wrong statement.

Three identical capacitors $C_1, C_2$ and $C_3$ have a capacitance of $1.0 \mu F$ each and they are uncharged initially. They are connected in a circuit as shown in the figure and $C_1$ is then filled completely with a dielectric material of relative permittivity $\varepsilon_r$. The cell electromotive force (emf) $V_0 = 8 \ V$. First,the switch $S_1$ is closed while the switch $S_2$ is kept open. When the capacitor $C_3$ is fully charged,$S_1$ is opened and $S_2$ is closed simultaneously. When all the capacitors reach equilibrium,the charge on $C_3$ is found to be $5 \mu C$. The value of $\varepsilon_r = . . . . $