Capacitors Questions and Answers

2 53 The distance between the plates of a charged plate capacitor disconnected from the battery is 5cm and the intensity of the field in it is E 300V cm An uncharged metal bar 1cm thick is introduced into the capacitor parallel to its planes The potential difference between the plates now is da s A 1500V B 1200V C 900V D zero

2 3 Two conducting objects one with charge of Q and a with Q are kept on x axis atx 3 andx 4 respective electric field on the x axis is given by 30 capacitance C of this configuration of objects Wha 3

Capacity of a parallel plate condenser can be increased by CARRERA OPTIONS MARK FOR REVIEW CLEAR SELECTION OA O B O C DY Increasing the distance between the plates Increasing the charge on the plates Decreasing the area of the plates Decreasing the distance botun

2 17 A 100 F capacitor is charged to 100V After the charging battery is disconnected The capacitor is then connected in parallel to another capacitor The final voltage is 20V Calculate the capacity of second capacitor

No 44 The charge flowing through the cell on closing the key k is equal to e 1 2 4CV 3 43 CV C HIC HIC

Two capacitors are connected with inductor as shown in figure potential difference across the capacitors are VA VB V0 Vc V 7 Initial current in circuit is zero If energy stored in capacitor 3C when current in inductor is maximum is aCV2 then a is 2 30 B 000000000 20

A parallel plate capacitor C has a charge q and potential V between the plates Work required to triple the distance between the plates is O CV 12 03 32 CV CV

Three capacitors with capacitance equal to 6 F 6 F and 3 F respectively are connected in series with 20 volt line Find the charge on 3 F kunki 6 F 6 F 3 20 13 GRI 6 F 6 uF 3 uF 20 V OPTIONS MARK FOR REVIEW CLEAR SELECTION OA 20 C OB 30 C OC 40 C OP 50 C 4

3 Two identical metal plates are given positive charges q and q q 9 If they are now brought close together to form a parallel plate capacitor with capacitance C the potential difference between the two plates will be and atte 9 1 9 9 C at e Pava 2 BARR E Fut A 9 92 2C 3 91 9 C 4 9 92 2C

Consider the shown network the capacitor C 6 F has an initial charge C C 4 F and R 80 0 Initially C is uncharged At t 0 the switch 90 30e e 1 S is closed The charge on C in C at t 192 us is x then value of is 2 S R

In the circuit shown in the figure the potential difference between A and B is 100 V The potential difference across the 6 F capacitor is A B 11 40 V 60 V 10 F 80 V Read More 6 LF 4 F

A capacitor of capacitance 8 F is connected in a circuit as shown in the figure Charge on the plates of the capacitor is 8 F HH 492 wwww 5 V 32 C 64 C 4 C 2092 wwwww wwwww 1Q

After a long time switch is swapped from 1 to 2 at t 0 The time when energy on capacitor and inductor will be same for the first time is LC Find n n reeeeeeee Answer 0 01 02 03 04 05 06 07 08 09 0 01 02 03 04 05 06 07 8 09

Consider the shown network the capacitor C 30e 6 F has an initial charge q C C 4 C e 1 F and R 80 Initially C is uncharged At t O the switch S is closed The charge on C in C at t 192 us is x then value of is S R www Answer 01 02 03 04 05 06 07 08 09 00 01 02 03 04 05 06 07

The capacities of three capacitors are in ratio 1 2 3 Their equivalent capacity when 60 UF connected in parallel is 11 more than that when they are connected in series The individual capacitors are of capacities UF

Suppose you need a capacitor bank with a total capacitance of 0 750 F withstanding 160 V but you have only 1 50 mF capacitors withstanding 40 V at your disposal What is the smallest number of capacitors you could connect together to achieve your goal and how would you connect them a 200 Ob 400 c 800 d 8000 1

A parallel plate capacitor is connected to a battery which builds up an electric field of 60 V cm between the plates as shown in figure I Now two initially neutral plates that are connected are positioned as shown in figure II The plates are at equal distances from each other Find the electric field strength between the plates B and D A B C A D B HIL

A potential difference of 220 V is maintained across a 12000 2 rheostat as shown in the figure The voltmeter V has resistance of 6000 2 and the point c is at one fourth of the distance from a to b The reading of voltmeter is 220V 55 V b a wwwwwwwwwww 50 V V 1

Three uncharged capacitors are connected with a batter as shown in the figure The work done by the battery in fully charging the capacitors will be 6 F 6 F 3 uF HE 0 6 J 10 V 0 3 mJ 0 3 J I

9 Four identical plates of surface area A are placed parallel to each other at equal distance d as shown in the figure The space between 2nd and 3rd is filled with a dielectric of dielectric constant K 2 The capacitance of the system across terminals A and B is A 1 2 A d alloy n 2 olog Eo A 8 drobiano B

A capacitor of capacitance C charge with Qo now it Qo connected across a battery of e m f V C positive plate of capacitor connected with ve end of battery and ve plate with ve end of battery then find energy supplied by battery before steady state condition obtained to capacitor is A B C 2C such that My Answer

A broadcast circuit can broadcast at 300 Mhz band A condenser of capacitance 2 4 F is available The value of the inductance required for resonant circuit is a 10 4 H b 10 7 H c 10 6 H d 10 2 H

Network shown find the value of capacitance c is the eq uivalent capacitance between points a and b is to be 1 mic ofarad are ready all capacitance are in micro Faraday Ao C H C 8 C 2 C HH 1 C5 6 C 2 Co C4 HH 12 4 OB

A parallel plate air capacitor is charged by a battery of emf then it is disconnected from the battery and allowed to discharge through a dielectric slab of dielectric constant K and resistivity p as shown in figure There is a uniform outward magnetic field B as the location of the capacitor The total momentum attained by the slab after complete discharge is A C El B P El B Ko B B kl D B ol e Square plate of s OB

After a long time switch is swapped from 1 to 2 at t O The time when energy on capacitor and inductor will be same for the first time is LC Find n n V 1 2 C reeeeeeee Answer 0 01 02 03 04 05 06 07 08 09 0 01 02 03 04 05 06 07

After a long time switch is swapped from 1 to 2 at r 0 The time when energy on capacitor and inductor will be same for the first time is LC Find n Answer 0 mim 02 O 05 07 O 00 6

A parallel plate capacitor having circular plates of radius 2 cm has a 100 V DC applied to it plates The plates are separated by 3 cm The space between the plates is filled with an o dielectric with 2 2 Calculate the electrical energy density and the energy stored in betwee the capacitor plates 5 marks

Capacitance of a parallel plate capacitor as shown in figure is A P d A 2d 500 Ad

A capacitor is having a capacity of 2 pF Electric potential across the capacitor is changing at the rate of 10 2 V s 1 The displacement current is 2 A 4 A O 6 A 10 A

as the capacity is equals to c q v EA d k 0A d Then shouldn t the answer be all in this question oose the correct answer The capacity of parallel plate condenser depends o 1 The separation between the plates 2 The potential applied across the plates 3 The amount of charge 4 Both 2 and 3

such that spring gets compressed by a length x and then released from rest Find the work done on the block A by the spring by the time the spring acquires its natural length Consider the circuit shown in the figure Capacitors A and B each have capacitance C 2 F The plates of capacitor A are shorted using a wire of resistance R 1 while the left plate of capacitor B is given an initial charge Q 4 C The switch is closed at a time t 0 What will be the initial current in ampere drawn from the battery immediately after the switch is closed www R R Q B T E 4Q C

26 Section AB of an electrical circuit shown in the figure If C 1 F C 2 F E 10 V and VA V 10 V then charge on the capacitor C will be C C A 20 1 HC 3 10 C E 40 10 B 2 HUC 4 Zero 8 Haz Medica 1 3 hom wh in t

2 Two large parallel conducting plates are given charges Q and Q respectively as shown in the figure Find the charge flown through the switch after the switch is closed Q Or too awoda plugit ouT nuble ohlodle ans 3 erli ale s bris V 1 Q Q towards the plate 2 Q towards ground 3 Q towards ground

A parallel plate capacitor with a Polymide dielectric has a capacitance of 440 nF and plate separation of 2 83 mm What is the magnitude of the greatest charge the capacitor can store on each plate before breakdown in units of coulombs Polymer Dielectric Strength V um 200 200 220 Polyethylene LD Polyethylene HD Polyethylene XL Polypropylene Biaxially oriented Polystyrene Polytetrafluoroethylene Poly vinylidene fluoride Polycarbonate Polyester Polyimide Froxy resin 200 200 88 176 10 2 252 300 280 25 45

A capacitor with capacitance 1 F and initial stored energy is 0 5 Joule is discharged through a resistance R 1 10 The charge on the capacitor the current through the resistor and the potential difference between the capacitor after t seconds are A charge on capacitor is 10 3xe B Current in resistor is 10 xet C Current in resistor is 10 3 xet D potential difference across the capacitor is 10 xet

d is filled with a dielectric of dielectric constant K 2 and thickness d 3 The effective capacitance of the capacitor will be A O 1 6 d 2 3 A 2d

We consider a parallel plate capacitor with area S and thickness d as shown in the figure below The dielectric between the plates has a relative permittivity of E 3 1 Calculate the relative permittivity required for a capacitor with same area S and a smaller thickness d d 2 4 so that the capacitance remains the same S Ex d

igure I 17 Two parallel plate capacitors of capacitances C and 2C consisting of plates of identical dimensions are connected with an ideal battery of terminal voltage Vas shown in the figure I Now the capacitor smaller in volume is completely inserted into the larger capacitor and kept in symmetric position and then connection polarities of the plates are reversed as shown in the figure II Which one of the following statements is correct a Charge flown through the battery is 8CV and it absorbs energy b Charge flown through the battery is 8CV and it delivers energy c Charge flown through the battery is 7CV and it absorbs energy d Charge flown through the battery is 7CV and it delivers energy

THI R C 10 V 16 The figure shows part of a large network in which potentials of some of the points are shown Each capacitor has a capacitance 5 F Which of the following statements is are true a From the given information potential of point O can be determined but that of B cannot be determined b From the given information potential of both the points O and B cannot be determined c If charge on capacitor C were also specified potential of point O can be determined but that of B cannot be determined d If charge on capacitor C were also specified potentials of both the points O and B can be determined

Equivalent capacitance between points A and B as shown in the following circuit will be 2C 2C 2C 2C 1 C 3 3C A C C 2 20 4 4C B

2 294 2 38 A capacitor is made of a flat plate of area A and another mF are plate is bent at four points and placed above the flat plate as shown in figure 2 297 Dimension of both the plates are shown in figure Find the capacitance of this structure between the two plates m A a 2d 3a Figure 2 297 a 3d

A parallel plate capacitor is charged such that electric field between the plates of capacitor is E The energy density of the capacitor is 2C 1 2 cv E 1 2

An uncharged capacitor is fully charged with a battery The ratio of energy stored in the capacitor to the work done by the battery in this process is 1 1 2 1 1 2 2 3

A parallel plate capacitor of capacitance C has been charged upto potential V The plates of this capacitor are connected to another identical uncharged capacitor The common potential acquired by the system is 2 V 2V Zero

Three uncharged capacitors are connected with a battery a shown in the figure The work done by the battery in fully charging the capacitors will be 6 F 6 F 3 uF HH 0 6 J 10 V 0 3 mJ 0 3 J 0 6 mJ

n identical capacitors are connected in series between points A and B as shown in the figure The effective capacitance between points A and B is C HB CCC AHHHH nC n c 310

A parallel plate capacitor has a uniform el field E in the space between the plates If the distance between the plates is d and the area of each plate is A the energy stored in the capacitor is 0 permittivity of free space 1 2 3 E Ad 20 12 0E EAd IN Eo

An uncharged parallel plate capacitor having a dielectric constant K is connected to a similar air cored parallel plate capacitor charged to a potential Vo The two share the charge and the common potential becomes V The dielectric constant K is V 1 Vo 1 V 1

2 The transistor shown in the figure has parameters VTN 0 4 V Kn 0 4 mA V and 2 0 The transistor is biased at Ino 0 8 mA a What is the maximum voltage gain b What is the bandwidth V 25 V Ro 2130 C 1pF

In parallel plate capacitor a dielectric slab is tightly inserted and charged by a battery Now capacitor is disconnected from battery and slab is slowly taken out If U was energy stored in capacitor with dielectric slab then the work done in pulling out the slab is 1 U 2 K 3 KU 4 K 1 U Find the reading of ammeter connected in the telegram neetques