Question

Find the total capacitance and total charge on the capacitors

• A. 1.5 nF, 9 nC
• B. 3.0 nF, 18 nC
• C. 1.5 nF,4.5nC
• D. 3.0 nF,9nC
• E. 3.0 nF, 4.5 nC

Answer 1

Answer: (A)

3 capacitors connected with a 6V battery as shown in the figure below

$\therefore$ Equivalent capacitance of $1nf$ and $2nF$ connected in parallel is given as, $C^{\prime }=(1+2)nF$
This equivalent $C^{\prime }$ is connected in series with $3nF$. So, the equivalent capacitance of the given circuit is
$C_{eq}=\frac{(1\times 2)\times 3}{(1+2)+3}=1.5nF$
Total charge on the capacitors $=V\times C_{eq}$
$=6\times (1.5nF)=9nC$