Physics for IIT-JEE 2012-2013: Electricity & Magnetism

904 Pages·2012·42.62 MB·English

R. K. MALIK’S JEE (MAIN & ADV.), MEDICAL
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for IIT-JEE 2012-13
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Physics for lIT-lEE
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ELECTRICITY & MAGNEETISM
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PhysIcs for 11T·JEE 2012·13: © 2012, 2011, 2010 Cengage learning India Pvt.ltd.
Electricity & Magnetism
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lSBN·13: 978·81·315·1489·4 S
ISBN· to: 81·315·1L489·7
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First Impression 2012
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Brief Contents
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Chapter 1 Coulomb's laws and Electric Field
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Chapter 2 Electric Flux and Gauss's law
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Chapter 3 Electric Potential I
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Chapter 4 Capacitor and Capacitance
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Appendix Ai Miscellaneous AssignLments and Archives on Chapters 1-4 .
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Chapter 5 E lectric Current and Circuits
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Chapter 6 Electrical Measuring InsNtruments
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Chapter 7 Heating Effects of Current

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Chapter 8 Faraday's law and lenz's law

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ChaEpter 9 Magnetics

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Chapter 10 Alternating Current

Appen dix A2 Miscellaneous Assignments and Archives on Chapters 5-10
Appendix A3 Solutions to Concept Application Exercises
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Contents
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Chapter 1 Coulomb's Laws and Electric Field K1.1 Exercises
1.33
Electric Charge SubjecStive Type 1.33
I 12
Objective Type
Charging of a Body 1.2 1.36
Work FUllction of a Body 13 SMliltiple Correct AlI,lwel's Type J.i4G
L Assertion-Reasoning Ty,Je
Charging by Friction 13 /A/
Charging by Conduction 1.3A Comprehension Type 1.42
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Charging by Induction 13 Matching CIoll/IIIII Type 1.44
Properties of Electric Charge L AII,m'ers (//u/ SOllllioll.\' 1.45
1.3
Quantization of Charge M Subjective Type 1.45
13 H
Conservation of Charge C Objective Typc: 1.5/
1.3
Additivity of Charge Mulliple Correcl AlISwers Type 1.5?
1.4 C
Charge is Invariant A,\'SCl'lioll-Rcmsonillg 7j>pe 1.57
1.4
Coulomb's Law . Comprehension Type 1.57
1N.6
Coulomb's Law in Vector Form N 1.6 Male/lillg COIUIIIII Type 1.6(j
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Superposition, P rinciple A 1.7 Chapter 2· Electric Flux and Gauss's law 2.1
Electric Field O 1.12
H ow to Measure Electric Field R 1.13 Electric Flux 2.2
Electric Field IntensiTty E 1.13 Gauss's Law 2.6
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Lines of Force 1.l6 Field ora Charged Conducting Sphere 2.7
Properties ofWElcclric Lines of Force 1.17 Selection of Gaussian Surface 2.7
R Different Patterns of Electric Field Lines 1.l7 Electric Ficld Outside thc Sphcre 2.7

Field of REing CI13rge U8 Electric Ficld Inside the Sphere 2.8
Field ofUnifonnly Charged Disk 121 Field of a Line Charge 2.8

FieNld ofTwo Oppositely Charged Shects 1.22 Selection ofG<1ussi<11l Surface 2.8
Electric Dipole 125 Field of an Infinite Plane Shcet of Charge 28

Electric Field duc to a Dipole 1.26 Selection of Gaussian Surface 2.8
Electric Field Intensity due to an Electric Dipole at a Field at the Surfllce ofa Conductor 2.9

Point on Ihe Axial Line 1.26 .•r .icldofa UnifonlllyChnrgcd Sphere 2.9
Electri.c Field Intensity due to an Electric Dipole Sclcction of Gauss inn Surfacc 2.9
at a Point on the Equatorial Line 1.26 Electric Field Inside the Sphere 29
Electric Field Intensity due to a Short Eleclric Field due to a Long Unifonllly
Dipole at Some General Point 1.27 Charged Cylinder 2.10
Net Force on a Dipole in a Non-UnifOnll Field 1.28 Electric Field Nc.1r Unifonnly Volume
Dipole in a Unifonn Electric Field 1.28 Charged Plane 2.10
Solved Examples 1.29 Field Inside the Plane 2.10
Appendix
2.11
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6 Contents
Solved Examples 2.13 Assertion-Reasoning Type 3.43
Exercises 2.17 ComprehellSion Type 3.44
Subjective Type 2.17 Matching COIIIIllII Type 3.47
Objective Type 2.18
Chapter 4 Capacitor and Capacitance 4.1
-Multiple Correct Allswers Type 2.21
Assertion-Reasolling Type 2.21
Capacitor 4.2
Comprehension Type 2.22 S
Units ofCapacitancc 42
Matching Colllllln Type 2.25
Pantllel Plate Capacitor S 42
Allswer.s and SOlllliolls 2.25 '
Capacitance of a Spherical Conductor or Capacitor 4.3
Subjective Type 2.25 Ene~gy' Stored in a CEharged Conductor or Capacitor 4.3
. ObjecliveType 2.28 K
Forcc Between the Plates of a Parallel Plate Capacitor 4.3
'Multipre Correct Answers Type 2.29
Energy DensSity (Energy Per Unit Volume) in Electric Field 4.4
Assertion-Reasoning Type I2.30
Loss of Energy During Redistribution of Charge 4.4
Comprehension Type 2.30
Combin.1StionofCapacitors 4.8
Matching COIUIIIII Type L 2.32 Capacitors Connected in Series 4.8
Chapter 3 Electric Potential 3.1 AEnergy in Series Combination 4.8
A Capacitors Connectcd in Parallel 4.8
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Electric Potential lind Energy 32L Energy in Parallel Combination 4.9
Electric Potential Energy of Two Point MCharges 32 Kirchhoff's Rules for Capacitors 4.12
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Electron-VOlt C33 Sign Convention 4.12
Electric Potential 33 Dielectric 4.14
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Equipotential Surface 3.4 Dielectric Constant 4.14

Relation Between Electri.c Field and Potential 3.5 Dielectric in an Electric Field 4.14
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Finding Electric Field from Electric Potential 3.5 Induced Charge on the Surface of Dielectric 4.14
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Electric PotentialK of Some Continuous Charge Distributions 3.7 Dielectric Breakdown 4.15
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A Charged Conducting Sphere 3.7 Capacity of Parallel Plate Capacitor with Dielectric 4.16
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A Non- Conducting Solid Sphere · 3.7 Force on Dielectric Slab at Constant
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A Unifonn Line of Charge 3.8 Potential Difference 4.17
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A R.ing ?fCharge 3.8 Effect of Dielectric on Different Parameters 4.18
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Charged Disk 3.9 Spherical Capacitor 4.18
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R.Potential due to an Electric Dipole 110 Cylindrical Capacitor 4.19
Work Done in Rotating an EleclTic Solved Examples 4.21
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Dipole in a Uniform Electric Field 3.10 Exercises 4.25
Potential Energy of an Electric DiJ? Ole Subjective Type 4.25
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In a Unifonn Electric Field 3.11 Objective Type 4.26
Solved Example• • 3.12 MlIltljJle Correct Answers Type 4.34
Exercise,~ 3.18 Assertion-Reasoning Type 4.35
Subjective Type 3.18 Comprehension Type 4.36
Objective Type 3.20 Matching Coilimll Type 4.39
Multiple Correct Allswers Type 3.26 Answers and Soilltions 4.40
Assertion-Reasoning Type 3.27 Subjective Type 4.40
Comprehension 1}pe 3.27 Objective Type 4.49
Ma}ching ColuliIlI Type 3.31 Multiple Correct Answers Type 4.49
AI/swers and Solllt;OIlS 3.33 Assertion-Reasoning Type 4.50
Subjective Type 3.33 Comprehension Type 4.50
Objective Type 3.38 Matching Coilimn Type 4.45
Mllltiple Correct AI!swers Type 3.43
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Contents 7
Appendix Al Miscellaneous Assignments and Charging of the Capacitor- Other Approach 5.29
Archives on Chapters 1-4 AI.I Equivalent Time Constant 5.32
Solved Examples 5.34
Exercises A1.2 Exercises 5Al
Objective Type AI.2 Subjective Type 5.42
Multiple Cprrect Answers Type A1.I6 Objective Type 5A5
Assertion-Reasoning Type AI.21 Mul/li)le CSorrect Answers Type 5.56
Comprehension Type AI.n Assertion-Reasoning Type 5.59
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Matching Column Type AI.33 Com'prehellsiol1 Type 5.59
Archives A1.37 Matching CO/limn Type 5.61
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Answers and SOlllliolls AJ.44 KAnswers and SOluliolls 5.61
Objective Type AIA4 Subjective Type 5.61
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Multiple Correct Answers Type A1.I57 Objective Type 5.67
Assertion-Reasoning Type A /.61 MIi/lli)le Correct AnslVers Type 5.76
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ComplT!hensioll Type LAI.63 As.\'enion-Reasol1ing Type 5.79
Malching Column Type AI.?3 Comprehension Type 5.80
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Archives A AI.75 Matching COII/IIII1 Type 5.82
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Chapter 5 Electric Current and Circuits 5.1 Chapter 6 Electrical' Measuring Instruments 6.1
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Electric Current C5.2 Galvanometer 6.2
Statement of Ohm 's Law 5.2 Ammcter 6.2
Current Density 5J Why SChould the Needle Deflect When There is Current? 6.2

Drift Velocity . 5.5 Problem in Using Galvanometcr itscJfns an Ammeter 6.2
Relation Between Drift Velocity and Current 5.5 NConversion ofa Galvanometer into an Ammeter 6.2
A Structural Model for Electrical Conductor N 5.7 Maximum Cuttent an Ammeter can Read 6.3
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Mobility 5.8A Modification of Ammeter to Obtain Other Range 63
Temperature Coefficient of Resistivity O 52 Voltmeter 63
Temperature Coefficients of Resistance 5.8 Unsuitability of the Galvanometer as Voltmeter 63
Finding Coefficient of Resistance R5.9 Conversion ofGalvanomcter inloa Voltmeter 6.4
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Validity. and Failure of Ohm's Law 5.10 Modifying Voltmeter to have Desired
Electromotive Force and Potential Difference 5.11 Rangc(say 0 to V) 6.'
Difference Between e.m.Wf(E) and Potential Differcncc( V) 5.12 Potentiometer 6.6
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Internal Resistance ofa Cell 5.12 COIllJ)<1rison of e.m.f.s of Two Cells Using Potentiometer 6.6
Combination of ReEsistances 5.13 Delenninalion of Internal Resistance ora Cell 6'.6
Resistances in Series 5.13 Meter Bridge or Slide Wire Bridge 69

ResistancNes in Parallel 5.13 Construction 6.9
Voltage Divider 5.13 Checking of Connections 6.9
Current Divider for Two Res istances 5.13 Working 6.9
CUfTCnt Divider for Three Resistances 5.14
Solved Examples 6.11
Calculation of Effect ive Resistance 5.14
Exercises 6.13
-Kirchhoff's 4w: Kirchhoff's Laws For , "
Electrical Networks 5.18 . Subjective Type 6.13
Wheatstone Bridge: Balanced Objective Type 6.15
Wheatstone Bridge .5.21 MII/lli)/e Correct A I1SlVers Type 6.20
Combination of Cells 5.22 Assertiw-Reasoll;lIg Type 6.21
Series Grouping 5.22 Comprehension Type 6.22
Parallel Grouping 5.22
Matcltillg CO/UIIIII Type 6.23
Mixed Grouping 5.23
Superposition Principle 5.23 Answers and Solutions 6.23
Concepts 5.23 Subjective Type 6.23
Charging 5.27 Objective Type 6.26
Time Constant (t) 5.28 Multiple Correct Allswers Type 6.30
Discharging 5.28 , - ,. .
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8 Contents
Comprehellsion Type '6.31 Exercises 8.'
Matchillg COIUIIIII TYIJe 6.31 Subjective TJpe 8.4
Objective Type 8.4
Chapter 7 Heating Effects of Current 7.1
Multiple Correct Answers Type 8.;
Heating Effect of Current 7.2 Assertion·Reasoning Type 8.;
Calise of Heating 7.2 Comprehension Type 8.:
Heat Produccd by an Electric Current 7.2 SMatching ColI/mil Type 8.!
Electric Powcr Produced in the Circuit 72
Archives 8.!
Units of Electric Ellergy and Electric Power 7.2 S
' Answers Gild Solutions 8.!
Maximum PowerTnmsferTheorem 7.5
Some Applications 7.5 Subjcclil'cE Type 8.~
Solved /:'x.~mple.\· K7.8 Objeclil'e Type 8./1
Multiple Correct Answers Type B.l.
Exerci.~e.~ 7./3 S
Subjeclive Type I 7.13 Assertion-Reasoning Type 8.!.
Objective Type 7.14 SComprehension Type 8.1.
Multiple Correct AI1.~wers Type L 7./9 Matching Colullln Type 8.1
Assertio1l-Reaso1lillg TJ'IJe 7.20 Archives 8.1
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Comprehel1sioll Type A 7.20
Chapter I9 Magnetics 9
Mflichillg Column l}~ L 7.22
Answers wu/ SO/iltiom' . M 7.22
Introduction
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Subjective Type C 7.22 Right Hand Rules for Determining the Direction of t
Objecfil'e Type 7.25 Magnetic Force Acting on a Moving Charged Particle
MII/tiple Correct AlIslVel:~ Type 7.31 CMotion of a Charged Particle in a Magnetic Field

Path of a Charged Parlic1e in Doth Electric and Magnetic
Assertion-R.eosonil1g Type 7.31
N Fields
Comprehellsiol/ 01Je 7.32
N Foree on a Currcnt Canying Wire 9
MatcKhing COIIIIIII! Type 7.34 . Direction ofForcc on a Current Carrying Wire in
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Magnetic Field 9
Chapter 8 Faraday's OLaw and Lenz's Law' 8.1
Forcc Between Two Infinite Parallel Current Carrying
Magnetic Flux R 8.2 Wires S
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. Faraday's J.1W of Electromagnetic Induction 8.3 Magnetic Dipole and Dipole Moment S
Direction oflnduced e.m.f. 83 Torque on a Current Carrying Planer Loop in a
Lenz's law W 8.3 Unifonn Magnetic Field ~
R Direction of the Induccd Current in a Circuit 8.3 Magnetic Field Due to a Moving Charge

MotioEnal Electromotive Force 8.10 and Current Carrying Wire
Magnetic Field ofa Moving Charge
Rotation ofa Conducting Rod in Constant Magnetic Field
Magnetic Field ofa Current Element
8.14
N Magnetic Field Due to Current in a Straight Line
Motional e.m.f. when the Magnetic Field is Non·uniform 8.15
Induced Electric Field and Inductance 8.20 Right Hand Thumb Rule
Magnetic Field althe Center of a
Induccd Elcctric Ficld: Induced e.m. f. in a Stationary
Current Carrying Arc
Conductor 8.20
Time-vary ing Magnctic Field &20 Magnetic Field of a Circular Current Loop
Mutual Inductancc 8.23 Magnetic Field on the Axis ofa Solenoid Having N
Turns Per Unit Length and Carrying a Current I
Self-Inductance 8.24
Application ofthe Kirchhoff's Law 8.25 Magnctic Field B at Point p. at a Distance R From the Centf
Series and Parallel Comi)ination ofInductors 8.25 a Flat Strip of Width 'a' Along its Perpendicular Disector
Parallel Combination 8.25 Ampere's Law
Combination of Inductors With Rcsistors 8.27 Field of a Long, Straight. Current Carrying Conductor
RiseofCurrent 827 Selection of Ampere Loop
Decay of Current 8.28 Magnetic Field BOutside and Inside a Cylindrical Wire
Energy Stored in Magnetic Field of an Inductor 8.31 Magnetic field of an Infinite Sheet of Given Linear Current
LCOscillntions 8.33 Density
So/IJC(/ Exdmples 8.38 Field ofa Long Solenoid
Selection of Amperian Loop for a Long Solenoid
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Contents £
Application of Ampere's Law 9.38 Objective Type 10.31
Solved Examples 9.44 Multiple Correct Answer.\' Type 10.31
Exercises 9.54 A.fserlion-Reasoning Type 10.31
Subjective 'TYpe 9.54 Comp/'ehens/oll Type 10.4(.
Objective Type 9.56 Matching Column Type 10.43
Multiple Correct Answers Type 9.81
Appendix A2 MisceUaneous Assignments and
Assertion-Reasoning Type 9.86
Comprehension Type 9.88 ArchiSves on Chapters 5·10 A2.1
Matching Column 'TYpe 9.96 Exercises S A2.2
Archives 9.99 '
Objective Type A2.2
Answers and Solutions 9.106
Multiple CorreEct Answers Type A2.15
Subjective TYpe 9.1K06
Assertion-Reasoning Type A2.19
Objective 1Ype 9.111
CompreShension Type A2.21
Multiple Co/'rect Answe/'s Type I9.131
Malching CO/IIIIIII Type A2.25
Assertion-Reasoning Type 9.137
ASrchives A2.26
Comprehension Type L 9.138
Answers and SOlliliolls A2.31
Matching Column Type 9.145
A Objective Type A2.31
Archives A 9.148
Multiple Correct Answers Type A2.41
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L Assert/ol/-Reasoning Type A2A5
Chapter 10 Alternating 10.1
CM~rrent
ComprehenSion Type A2.46
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Alternative Current and Voltage C, 102 Matching COIIIIIIII Type A2.49
Phasor Diagrams 102
Archives A2.75
Average or Mean Value of Altemating Current IOJ C

Root Mean Square (rms) Values 10.3 Appendix A3 Solutions to Concept Application
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Resistance and Reactance 10.N4 Exercises A3.1
Resistor in an AC Circuit N 10.4
Inductor in aKn AC Circuit 10.5
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Meaning of Inductive Reactance 10.5
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Capa citor in an AC Circuit 10.6
Caution R 10.6
Meaning of CapacitivTe Reactance 10.7
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Resistor And Capacitor in an AC Circuit 10.7

Comparing AC CWircuit Elements 10.7
R L-R-C Series Circuit 10.8
Meaning of Impedance and Phase A ngle 109
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Power in Alternating-Current Circuits 10.12
Power in a Resistor 10.12
PowNer in a General AC Circuit 10.12
Choke Coil 10.13

Circuit Behavior at Resonance 10.13
Transformers ·10.14
How Transfonn ers Work 10.14
Exercises /0.15
Subjective IYpe 10.15
Objective Type 10.16
Multiple Correct Answers Type 10.23
Assertion-Reasoning Type 10.24
Comprehensioll Type 10.24
Matching Columll Type 10.26
AII~wers alld Solutions 10.27
Subjective Type 10.27
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R. K. MALIK’S JEE (MAIN & ADV.), MEDICAL
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Office.: 606 , 6th Floor, Hariom Tower, Circular Road, Ranchi-1,
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