Three capacitors each of capacitance $9 \;pF$ are connected in series.
$(a)$ What is the total capacitance of the combination?
$(b)$ What is the potential difference across each capacitor if the combination is connected to a $120 \;V$ supply?

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) Capacitance of each of the three capacitors,$C = 9 \;pF$.
The equivalent capacitance $(C_{eq})$ of the combination of capacitors in series is given by the relation:
$\frac{1}{C_{eq}} = \frac{1}{C} + \frac{1}{C} + \frac{1}{C} = \frac{3}{C} = \frac{3}{9} = \frac{1}{3} \;pF^{-1}$.
$\Rightarrow C_{eq} = 3 \;pF$.
Therefore,the total capacitance of the combination is $3 \;pF$.
$(b)$ Supply voltage,$V = 120 \;V$.
Since the capacitors are identical and connected in series,the potential difference $(V')$ across each capacitor is equal to one-third of the supply voltage:
$V' = \frac{V}{3} = \frac{120}{3} = 40 \;V$.
Therefore,the potential difference across each capacitor is $40 \;V$.

Explore More

Similar Questions

Four metallic plates,each of surface area (of one side) $A$,are placed at a distance $d$ apart from each other. The two outer plates are connected to a point $P$ and the two inner plates are connected to another point $Q$ as shown in the figure below. Then,the capacitance of the system is

Three capacitors each of capacitance $C$ and of breakdown voltage $V$ are joined in series. The capacitance and breakdown voltage of the combination will be

Two capacitors of equal capacity are first connected in parallel and then in series. The ratio of the total capacities in the two cases will be

Two capacitors $C_1 = 2 \ \mu F$ and $C_2 = 3 \ \mu F$ are connected in series between points $A$ and $C$. The potential at point $A$ is $40 \ V$ and the potential at point $C$ is $10 \ V$. Find the potential at point $B$ (between the two capacitors). (in $V$)

What is the potential difference between points $A$ and $B$ in the circuit shown (in $V$)?

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo