BEGINNER'S BOX - 1

A capacitor of capacitance C has a charge Q The net charge on a capacitor is always.................  It stores.......................  energy.

Eight drops of mercury of equal radii and possessing equal charges combine to form a big drop. Then the capacitance of the bigger drop compared to each individual drop is  .........................

The capacitance of a spherical condenser whose inner sphere is grounded is $1 \mu \mathrm{F}$. If the spacing between the two spheres is $1 \mathrm{mm}$, then what is the radius of the outer sphere?

When $1.0\times {10}^{12}$ electrons are transferred from one conductor to another, a potential difference of $10 \mathrm{V}$ appears between the conductors. Calculate the capacitance of the two-conductor system.

The graph shows the variation of voltage $V$ across the 

plates of two capacitors $A$ and $B$ with charge $Q$.

Which of the two capacitors has larger capacitance?

For flash pictures, a photographer uses a $30 \mu \mathrm{F}$ capacitor and a charger that supplies $3\times {10}^3 \mathrm{volt}$. Calculate the charge and the energy spent for each flash.

Two capacitors $C_1$ and $C_2$ have an equal amount of energy stored in them. What is the ratio of potential differences across their plates?

A parallel plate capacitor has rectangular plates with dimensions $6.0 \mathrm{cm}\times 8.0 \mathrm{cm}$. If the plates are separated by a sheet of Teflon $\left(K=2.1\right)$ $1.5 \mathrm{mm}$ thick, how much energy is stored in the capacitor when it is connected to a $12 \mathrm{V}$ battery?