A parallel plate capacitor with air between the plates has a capacitance of 9 pF . The separation between its plates is ‘ d ’. The space between the p - Physics MCQ AIEEE 2026 | ExamTest.live | ExamTest.live

Home Tests Search Rank Profile

mediumMCQAIEEE2026Physics

1 mark

A parallel plate capacitor with air between the plates has a capacitance of 9 pF . The separation between its plates is ‘ d ’. The space between the plates is now filled with two dielectrics. One has k_{1} = 3 and thickness d /3 while the other has k_{2} = 6 and thickness 2 d /3 . Capacitance of the capacitor is now:

A $1.8 pF$
B $45 pF$
C $40.5 pF$
D $20.25 pF$

Solution & Step-by-step Explanation

Initial capacitance C_{0} = \frac{ϵ _{0} A}{d} = 9 pF .When filled with dielectrics in series, the new capacitance C^{'} is: \frac{1}{C ^{'}} = \frac{d _{1}}{k _{1} ϵ _{0} A} + \frac{d _{2}}{k _{2} ϵ _{0} A} \frac{1}{C ^{'}} = \frac{d /3}{3 ϵ _{0} A} + \frac{2 d /3}{6 ϵ _{0} A} = \frac{d}{9 ϵ _{0} A} + \frac{d}{9 ϵ _{0} A} = \frac{2 d}{9 ϵ _{0} A} C^{'} = \frac{9 ϵ _{0} A}{2 d} = 4.5 \frac{ϵ _{0} A}{d} = 4.5 \times 9 pF = 40.5 pF

Practice this question

Try it yourself before checking the explanation above.

A parallel plate capacitor with air between the plates has a capacitance of 9 pF . The separation between its plates is ‘ d ’. The space between the plates is now filled with two dielectrics. One has k_{1} = 3 and thickness d /3 while the other has k_{2} = 6 and thickness 2 d /3 . Capacitance of the capacitor is now:

A

1.8 pF

B

45 pF

C

40.5 pF

D

20.25 pF

Share This Question

electrostatics capacitors dielectrics

Related Questions

Which one of the following statements is true?

Which of the following statements is not correct?

Which one of the following statements is correct?

The product formed by the reaction of an aldehyde with a primary amine is:

Which part of the tobacco plant is infected by Meloidogyne incognita?

The term ecosystem was coined by:

Ready for a Full Test?

Practice with timed mock tests and track your performance across Physics.

Browse Tests Leaderboard

Discussion