If the potential difference across a capacitor is increased from $5 \,V$ to $15 \,V$, then the ratio of final energy to initial energy stored in the capacitor is

In a defibrillator,a $40\ \mu F$ capacitor is charged to $3000\ V$. If the stored energy of the capacitor is discharged through the patient during a pulse of duration $2\ ms$,what is the power delivered to the patient in $kW$?

If the charge on a capacitor is increased by $2 \ C$, the energy stored in it increases by $21 \%$. The original charge on the capacitor is (in $C$)

Three plates $A, B, C$ each of area $50 \, cm^2$ have a separation of $3 \, mm$ between $A$ and $B$ and $3 \, mm$ between $B$ and $C$. The energy stored when the plates are fully charged is (as shown in the figure):

Four capacitors each of capacity $2 \mu F$ are connected as shown in the figure. If $V_{A}-V_{B}=10 \,V$,the energy stored in the system is:

$A$ $6\,\mu F$ capacitor is charged from $10\,V$ to $20\,V$. The increase in energy will be: