Get 2 FREE Instant-Explanations on Filo with code FILOAPP

Home

Class 12

Physics

Electrostatic Potential and Capacitance

Combination of capacitors

Three capacitors having capacitances of 8.4 {F}, 8.2 {F} and

Question

Medium

Solving time: 3 mins

Three capacitors having capacitances of $8.4 μ F, 8.2 μ F$ and $4.2 μ F$ are connected in series across a $36 V$ potential difference.
(a) What is the charge on $4.2 μ F$ capacitor?
(b) What is the total energy stored in all three capacitors?
(c) The capacitors are disconnected from the potential difference without allowing them to discharge. They are then reconnected in parallel with each other, with the positively charged plates connected together. What is the voltage across each capacitor in the parallel combination?
(d) What is the total energy now stored in the capacitors?

Views: 5,551 students

Book:

Electricity and Magnetism (DC Pandey)

Found 2 tutors discussing this question

Owen Discussed

Three capacitors having capacitances of

8.4 μ F, 8.2 μ F

and

4.2 μ F

are connected in series across a

36 V

potential difference.
(a) What is the charge on

4.2 μ F

capacitor?
(b) What is the total energy stored in all three capacitors?
(c) The capacitors are disconnected from the potential difference without allowing them to discharge. They are then reconnected in parallel with each other, with the positively charged plates connected together. What is the voltage across each capacitor in the parallel combination?
(d) What is the total energy now stored in the capacitors?

8 mins ago

Discuss this question LIVE

8 mins ago

Text solutionVerified

(a)

\frac{1}{C _{net}} = \frac{1}{8.4} + \frac{1}{8.2} + \frac{1}{4.2}

∴ C_{net} = 2.09 μ F

q_{net} = C_{net} V

= (2.09) (36)

= 75.14 μ C \approx 76 μ C

In series, charge remains same in all capacitors.
(b)

U_{total} = \frac{1}{2} C_{net} V^{2}

(c)

q_{total} = (3) (76) μ C = 288 μ C

Now common potential in parallel,

V = \frac{q _{total}}{C _{total}} = \frac{228 μ C}{( 8.4 + 8.2 + 4.2 ) μ F}

(d)

U_{total} = \frac{1}{2} C_{net} V^{2}

Was this solution helpful?

110

Report

One destination for complete JEE/NEET preparation

One destination to cover all your homework and assignment needs

Learn Practice Revision Succeed

Instant 1:1 help, 24x7

60, 000+ Expert tutors

Textbook solutions

Big idea maths, McGraw-Hill Education etc

Essay review

Get expert feedback on your essay

Schedule classes

High dosage tutoring from Dedicated 3 experts

Trusted by 4 million+ students

Stuck on the question or explanation?

Connect with our Physics tutors online and get step by step solution of this question.

231 students are taking LIVE classes

Question Text	Three capacitors having capacitances of $8.4 μ F, 8.2 μ F$ and $4.2 μ F$ are connected in series across a $36 V$ potential difference. (a) What is the charge on $4.2 μ F$ capacitor? (b) What is the total energy stored in all three capacitors? (c) The capacitors are disconnected from the potential difference without allowing them to discharge. They are then reconnected in parallel with each other, with the positively charged plates connected together. What is the voltage across each capacitor in the parallel combination? (d) What is the total energy now stored in the capacitors?
Topic	Electrostatic Potential and Capacitance
Subject	Physics
Class	Class 12
Answer Type	Text solution:1
Upvotes	110

Text solutionVerified

Practice questions from Electricity and Magnetism (DC Pandey)

Practice more questions from Electrostatic Potential and Capacitance

Practice questions on similar concepts asked by Filo students

Text solutionVerified

Practice questions from Electricity and Magnetism (DC Pandey)

Practice more questions from Electrostatic Potential and Capacitance

Practice questions on similar concepts asked by Filo students

Related books for questions on Electrostatic Potential and Capacitance