Class 12 Physics Learning Resources

Welcome to the Class 12 Physics section.

About This Section of Class 12:

Here you will find chapter-wise notes, formula sheets, MCQs as well as conceptual explanations.

These resources are very useful for CBSE Board examinations as well as for building a strong foundation for NEET and JEE preparation. Every chapter is prepared in a simple and student-friendly manner.

The study material available here is prepared according to the latest NCERT syllabus and focuses on conceptual understanding rather than rote learning.

This page is created for CBSE Class 12 students and for aspirants preparing for NEET, JEE and other competitive examinations.

Physics in Class 12 plays a crucial role in Board examinations and competitive entrance tests. Therefore, every chapter is explained carefully with clear concepts, important formulas, diagrams and examination-oriented notes.

Image of Myself in Physics Lab:

About the Author:

The content has been prepared by Er. Birendra Pratap Singh, an experienced Physics educator who has been teaching senior secondary students for many years.

Syllabus of Class 12 Physics as per CBSE:

This page provides complete Chapter-wise Notes covering all major Chapters. It includes as per NCERT Book,

1. Electric Charges and Fields
2. Electrostatic Potential and Capacitance
3. Current Electricity
4. Moving Charges and Magnetism
5. Magnetism and Matter
6. Electromagnetic Induction
7. Alternating Current
8. Electromagnetic Waves
9. Ray Optics
10. Wave Optics
11. Dual Nature of Radiation and Matter
12. Atoms
13. Nuclei
14. Semiconductor and Electronics Devices

Each Chapter contains,

Inside each chapter, detailed notes are provided. Diagrams, figures and graphs are included.

Formula Sheets for quick revision are also available. These formula sheets summarize important equations and concepts in a simple format. It makes revision faster and more effective before examinations.

Every chapter also includes carefully selected MCQs that help students evaluate their understanding and prepare for CBSE Board examinations, NEET and JEE. Regular practice improves conceptual clarity, speed and accuracy.

Objective of this Section of Class 12 Physics:

The objective of this website is to make Physics easy, interesting and enjoyable for every learner. Students can use these resources for classroom learning, homework, revision and competitive examination preparation.

New notes, blogs, eBooks and educational resources will continue to be added regularly.

Whether you are aiming for high marks in the CBSE Board Examination or preparing for engineering and medical entrance examinations, this page offers reliable and high-quality study material to support your preparation.

Keep learning with confidence, revise regularly, solve practice questions and stay connected for the latest Physics resources.

Best Wishes for your academic success!

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Class 12 Physics Notes,Formula Sheet and MCQs

Chapter-wise

Chapter-1: Electric Charges and Fields

• Notes
• Formula Sheet
• MCQs
  Welcome to your Ch-1: Electric Charges and Fields

  1. 

  An electric dipole placed in non-uniform electric field experiences

  (a) Net force = 0, net torque = o

  (b) Net force = 0, Net torque ≠ 0

  (c) Net force ≠ 0, Net torque ≠ 0

  (d) Net force ≠ 0, Net torque = 0

  None

  2. 

  The net electric field at equatorial position at distance r from the centre of a dipole varies

  (a) directly proportional to r³

  (b) inversely proportional to r³

  (c) inversely proportional to r²

  (d) zero

  None

  3. 

  The electric field due to an infinite line charge at distance r is

  (a) directly proportional to r

  (b) inversely proportional to r

  (c) inversely proportional to r²

  (d) independent of r

  None

  4. 

  Indentify the incorrect option

  (a) Electric field lines never form a closed loop

  (b) Electric field lines do not cross each other

  (c) Electric field line is perpendicular on the surface of conductor

  (d) Electric field line is not a continuous line

  None

  5. 

  Two static and point charges – 2q and +q are situated at the origin and at the point (2a, 0 ,0) respectively. The point along x-axis where the electric field zero, is

  (a) at distance 2a from -2q outside

  (b) at mid point

  (c) at distance 2a outside from +q

  (d) at distance a from +q outside

  None

  6. 

  Charges q, -q, q and -q are placed at the corners A, B, C and D of a square.The direction of electric field at the centre of the square is along:

  (a) AB

  (b) zero

  (c) BD

  (d) AC

  None

  7. 

  Three identical point charges +q, -q and -q, are placed at the vertices of A, B and C of an equilateral triangle ABC of each side r. What is the direction of net electric field at the centre O of this triangle?

  (a) zero

  (b) along the line AO and away from centre

  (c) Along line OB and away from O

  (d) Along line OA and towards A

  None

  8. 

  What is the electric flux passes through a surface of area 100 m² lying in the y-z plane,if vector E = (i ̂+ 2j ̂+ 3k ̂ ) N/C ?

  (a) 100 Vm

  (b) 200 Vm

  (c) 300 Vm

  (d) zero

  None

  9. 

  A point charge q is placed at the centre of the semicircle.The flux of the electric field passing through this surface is:

  (a) Zero

  (b) q/ε₀

  (c) q/2ε₀

  (d) 2q/ε₀

  None

  10. 

  Two spherical conductors A and B having radii r and 2r and carying equal charges q are brought in contact and then separated. What are charges on each sphere after separation?

  (a) q on each A and B

  (b) q/3 on A and q on B

  (c) 2q/3 on A and 4q/3 on B

  (d) q/3 on A and 2q/3 on B

  None

  11. 

  Two point charges + 16 e and + 4e are at distance r apart. At what distance, a charge q must be placed from charge +4e so that it is in equilibrium?

  (a) r/3

  (b) 2r/3

  (c) r/2

  (d) 3r/2

  None

  12. 

  A dipole of point charges, q and -q are fixed at points (0, a) and (0, -a) on the y-axis. The magnitude of net dipole moment

  (a) qa

  (b) -qa

  (c) 2qa

  (d) -2qa

  None

  13. 

  A dipole (-q and +q) is placed on y-axis at position (0, -a) and (0, a). The direction of net electric field at equatorial position is

  (a) along the direction of dipole moment

  (b) opposite to the direction of dipole moment

  (c) perpendicular to the direction of dipole moment

  (a) none of these

  None

  14. 

  A dipole of moment p makes an angle 30⁰ with the electric field E. The torque acting on it will be

  (a) pE

  (b) pE/2

  (c) zero

  (d) pE√3/2

  None

  15. 

  Three point charges, each equal to -q are placed at the vertices of an equilateral triangle. A third charge Q is placed at the centre of the centre. Find the value of Q for all four charges are in equilibrium.

  (a) q

  (b) q/√3

  (c) -q/√3

  (d) q/2

  None

  16. 

  Two point charges -q and +q are placed at a distance r apart. A third charge Q is so placed that all three charges are in equilibrium. Then the value of third charge Q will be

  (a) -q

  (b) +q

  (c) q/2

  (d) -q/2

  None

  17. 

  Two infinite plane sheet M and N are parallel to each other and separated by some distance apart. The surface charge densities on A and B are +σ and -σ respectively. What is the electric field outside plate M?

  (a) σ/ϵ₀

  (b) zero

  (c) σ/2ϵ₀

  (d) None

  None

  18. 

  What is the direction of net electric field at the centre of a dipole?

  (a) towards positive charge

  (c) zero

  (c) kq/r²

  (d) Towards negative charge

  None

  19. 

  A dielectric of constant k is completely filled between two point charges. The force acting between them

  ((a) decreases k times

  (b) increases k times

  (c) remains unchanged

  (d) decreases k² times

  None

  20. 

  Four point charges q, q, -q and -q are placed at four corners of a square of each side 'a'. Find the net dipole moment of the system.

  

  (a) qa

  (b) 2qa

  (c) qa√3

  (d) qa√2

  None

  Previous Start Quiz Next
  

  Time’s up

Chapter-2: Electrostatic Potential and Capacitance

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-2-Electrostatic Potential and Capaitance

  1. 

  If the potential in a region is expressed as V= (3x +4y) in SI units, then the magnitude of electric field at point (0 m, 1 m, 0 m) will be:

  (a) 5 N/C

  (b) -5 N/C

  (c) 3 N/C

  (c) 4 N/C

  None

  2. 

  In which way to connect three condensers each of capacitance 1 μF in order to get the equivalent capacitance of (2/3) μF ?

  (a) all of them in series

  (b) all of them in parallel

  (c) two in parallel and one in series

  (d) two in series and one in parallel

  None

  3. 

  At what finite distance from a negative point charge (-q), the magnitude of electric field and electric potential is equal?

  (a) 0.5 m

  (b) 1 m

  (c) infinite

  (d) 1 cm

  None

  4. 

  What is the work done to move a point charge of 1 C from infinity to a point of potential 10 V?

  1 J

  9 J

  -10 J

  10 J

  None

  5. 

  What is the electric field at a distance 5 cm from the centre of a hollow spherical conducting shell of radius 6 cm having a charge of 2 mC on its surface?

  (a) 1.5 x 10¹⁰ V/m

  (b) 2.5 x 10¹⁰ V/m

  (c) 3.5 x 10⁻¹⁰ V/m

  (d) zero

  None

  6. 

  An electrical charge 2 x 10⁻⁸ C is placed at the point (1, 2, 4) m. At the point (4, 2, 0) m, the electric

  (a) potential will be 36 V

  (b) field will be along y-axis

  (c) field will increase if the space between the points is filled with a dielectric

  (d) all of the above

  None

  7. 

  Two concentric spherical shell have radii a and 2a. The charge on sphere of radius a is q and the charge on sphere of radius 2a is -q. What is the electric field at distance 3a from the centre of sphere?

  (a) Kq/2a

  (b) -Kq/a

  (c) zero

  (d) kq/3a

  None

  8. 

  What is the Electric field and the electric potential inside a spherical shell having charge q on the surface and its radius is R?

  (a) E = 0, V = 0

  (b) E = 0, V ≠ 0

  (c) E ≠ 0, V = 0

  (d) E ≠ 0, V ≠ 0

  None

  9. 

  When a dielectric material is introduced between the plates of a charged capacitor, then electric potential between the plates will

  (a) decrease

  (b) remain constant

  (c) increase

  (d) none of the above

  None

  10. 

  A point charge q is placed at the origin. Another charge -q is brought from infinity to a distance r from the point charge. The potential energy of the system is

  (a) -kq²/r

  (b) kq²/r

  (c) zero

  (d) kq²/r²

  None

  11. 

  It is given 3 capacitors each of capacitance 6 μ F. Connect all these in such a way to get equivalent capacitance of 9 μ F.

  (a) Two in series and one is parallel across the two

  (b) two in parallel and one is series with them

  (c) All three in series

  (d) All three in parallel

  None

  12. 

  The net electric potential at the centre of a square of each side 'a' and the charges placed at each corner are +q, +q, -q and -q, is

  (a) 4kq√2/l

  (b) kq√2/l

  (c) 4kq/l

  (d) zero

  None

  13. 

  A charge q is placed at the origin. The electric potential at a position (î – k̂) m is (k=1/4πε₀)

  (a) kq/√2

  (b) kq

  (c0 zero

  (d) -kq/√2

  None

  14. 

  The electric potential along the direction of electric field

  (a) increases

  (b) remains constant

  (c) decreases

  (d) may decrease

  None

  15. 

  The work done to move a charge on the equipotential surface

  (a) decreases

  (b) increases

  (c) remains constant

  (d) zero

  None

  16. 

  The equipotential surfaces' spacing between a dipole

  (a) decreases

  (b) increases

  (c) remains constant

  (d) zero

  None

  17. 

  The work done to rotate a dipole of dipole moment p from 0⁰ to unstable equilibrium in the uniform electric field of magnitude E is

  (a) pE

  (b) 2 pE

  (c) -pE

  (d) -2pE

  None

  18. 

  The work done by the conservative force is equal to

  (a) negative of potential energy

  (b) positive of potential energy

  (c) zero

  (d) none of these

  None

  19. 

  The capacitance of a parallel platecapacitor in air is C₀ and the capacitance with completely filled dielectric is C. The electric field in air is E₀ and inside the dielectric, the net field is E. Then dielectric constant K is

  (a) C₀/C

  (b) C / C₀

  (c) E₀/E

  (d) both (b) and (c)

  None

  20. 

  A conductor is completely filled between the gap of a parallel plate capacitor. Its capacitance is (d = separation of plates, t = thickness of conductor)

  (a) zero

  (b) infinity

  (c) ε₀A/(d-t)

  (d) none

  None

  21. 

  The potential in a region is given as V = x². The electric field at point x = 1 cm is

  (a) 0.02 î N/C

  (b) -0.02 î N/C

  (c) 2 î N/C

  (d) -2 î N/C

  None

  Previous Start Quiz Next
  

  Time’s up

Chapter-3: Current Electricity

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-3-Current Electricty

  1. 

  What is the charge on a capacitor of 10 μF connected in parallel with a battery of 10 V and also in parallel of resistor 10 Ω?

  (a) 10 μC

  (b) 200 μC

  (c) 100 μC

  (d) 10 μC

  None

  2. 

  The specific resistance of a conductor increases with

  (a) increase in temperature

  (b) increase in cross-sectional area

  (c) decrease in length

  (d) decrease in cross-sectional area

  None

  3. 

  The charge flows through a resistance 2 Ω in closed circuit varies with time t as q = t – t². The potential different across the resistance at t = 1 s will be

  (a) 2 V

  (b) -2 V

  (c) 4 V

  (d) -4 V

  None

  4. 

  A bulb is rated 100 W, 220 V. When it is connected with a battery of 110 V, the power of the bulb becomes

  (a) 100 W

  (b) 50 W

  (c) 200 W

  (d) 25 W

  None

  5. 

  Identify the wrong statement.

  (a) Charge is a vector quantity

  (b) Current is a scalar quantity

  (c) Static charge produces magnetic field

  (d) SI unit of current density is Am²

  None

  6. 

  The current in a conductor varies with time as I = 2t + 3 t² where I is in ampere and t is in seconds. Electric charge flowing through the conductor during t =1 s to t = 2 s is

  7 C

  10 C

  27 C

  44 C

  None

  7. 

  A resistance R is connected in series with an ideal voltmeter. The combination is connected with a battery of 10 V across it. The voltmeter will read

  (a) 10 V

  (b) zero

  (c) infinite

  (d) 8 V

  None

  8. 

  Current through a wire of resistance 10 Ω when connected across a battery of 12 V alongwith a closed switch in parallel of the resistance is

  (a) 1.2 A

  (b) 0.8 A

  (c) zero

  (d) infinite

  None

  9. 

  When temperature increases, the drift speed

  (a) increases

  (b) decreases

  (c) remains constant

  (d) zero

  None

  10. 

  A voltmeter connected with a resistance R in series and a battery of 10 V also connected in series of it. The circuit is open. The voltmeter will read

  (a) 10 V

  (b) zero

  (c) infinite

  (c) none of the above

  None

  11. 

  A cell of 12 V with neglible internal resistance is connected between two resistances of 2 Ω and 3 Ω. The potential difference across A and B as shown in the figure is

  

  (a) 1 V

  (b) 2 V

  (c) 2.4 V

  (d) 10 V

  None

  12. 

  As shown in the circuit, find the current.

  

  (a) 5/6 A

  (b) 1/2 A

  (c) 1 A

  (d) 6/5 A

  None

  13. 

  Three cells each 1 V, 2 V and 3 V are connected in parallel and the combination is connected with a resistance of 2 ohm across it. Find the current in the circuit.

  

  (a) 3 A

  (b) 3/11 A

  (c) 1 A

  (d) 1/3 A

  None

  14. 

  Two bulbs of 12 W and 4 W are once connected in parallel and then they are connected in series. The ratio of equivalent power of parallel to series will be

  (a) 16 : 3

  (b) 3 : 16

  (c) 4: 3

  (d) 3 : 4

  None

  15. 

  When galvanometer and battery are interchanged, the balancing of Wheatstone bridge

  (a) is not affected

  (b) is affected

  (c) will be unbalanced

  (d) None of these

  None

  16. 

  An galvanometer gives full-scale deflection when current of 1.0 A is passed in it. To convert it into 5 A range ammeter, the ratio of shunt to galvanometer resistance will be

  (a) 4 : 1

  (b) 1 : 5

  (c) 5 ; 1

  (d) 1 : 4

  None

  17. 

  Two resistors of 100 Ω and 200 Ω are connected in series. This combination is connected with a battery of 24 V. When a voltmeter of 100 Ω resistance is connected across 100 Ω resistor, then the reading of the voltmeter will be

  (a) 1.6 V

  (b) 1.0 V

  (c) 0.5 V

  (d) 2.0 V

  None

  18. 

  In a Wheatstone Bridge circuit, P = 5 Ω, Q = 10 Ω, R = 10 Ω, S = 5 Ω, G = 15 Ω. When switch is closed, find the current drawn from the battery of potential difference 13 V.

  

  (a) 1 A

  (b) 2 A

  (c) 3 A

  (d) 1.8 A

  None

  19. 

  The mobility is the ratio of

  (a) electric field to voltage

  (b) electric field to drift speed

  (c) drift speed to electric field

  (d) current density to electric field

  None

  20. 

  When collisions of electrons increases, the drift speed of electrons in a metal conductor

  (a) increases

  (b) decreases

  (c) remains same

  (d) first increases the decreases

  None

  Previous Start Quiz Next
  

  Time’s up

Chapter-4: Moving Charges and Magnetism

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-4-Moving Charges and Magnetism

  1. 

  Determine the current flowing through a circular loop of radius 2 m if the magnetic field at its centre is π tesla.

  (a) 2× 10⁶ A

  (b) 5× 10⁶ A

  (c) 2.5× 10⁶ A

  (d) 10⁷ A

  None

  2. 

  What is the maximum force acting on a positive charge particle moving with velocity vector v in the uniform magnetic field vector B?

  (a) zero

  (b) qvB

  (c) -qvB

  (d) qvB sin θ

  None

  3. 

  How can a glavanometer be converted in to a voltmeter?

  (a) Connecting high resistance in parallel with galvanometer

  (b) connecting low resistance in parallel with galvanometer

  (c) Connecting high resistance in series with galvanometer

  (d) Connecting low resistance in series with galvanometer

  None

  4. 

  To convert a galvanometer into an ammeter, we connect

  (a) high resistance in parallel

  low resistance in parallel

  high resistance in series

  low resistance in series

  None

  5. 

  Two ammeters one 10 A range and another 5 A range are given. Which one will have low shunt value?

  (a) 5 A ammeter

  (b) 10 A ammeter

  (c) both will have equal value of shunt

  (d) none of these

  None

  6. 

  Two voltmeters, one 5 V and another 3 V range are given. Which one will have high resistance?

  (a) 5 V voltmeter

  (b) 3 V voltmeter

  (c) both will have equal series resistance

  (d) none of these

  None

  7. 

  The magnetic field at the centre of solenoid is

  (a) equal to the value at ends

  (b) half the value at ends

  (c) double the value at ends

  (d) μ₀nI/2

  None

  8. 

  The direction of current in two long parallel wire is in opposite directions. The nature of force between them is

  (a) attractive

  (b) repulsive

  (c) no force acts between them

  (d) both attractive and repulsive

  None

  9. 

  Two long parallel wires carryig current will exprience magnetic force. If current equal to 1 A and seperation between wires is 1 m, then the magnitude of force on 1 m length ofany one wire is equal to

  (a) 4 π X 10⁻⁷ N

  (b) 2 X 10⁻⁷ N

  (c) 2 X 10⁷ N

  (c) 2 π X 10⁷ N

  None

  10. 

  If the angle between velocity of moving charge and uniform magnetic field is π/6, then the path of the moving particle will be

  (a) circular

  (b) straight line

  (c) ellipse

  (d) helical

  None

  11. 

  The radius of circular path is r amd charge q with mass m moving with velocity vector v in the dot magnetic field. Th radius is given by

  (a) r = mv/qB

  (b) r = qB/mv

  (c) r = m/qvB

  (d) r = qBm/v

  None

  12. 

  On what factors time period of a charge q moving with velocity vector v in the cross magnetic field does not depend?

  (a) q and v

  (b) q and B

  (c) v and B

  (d) r and v

  None

  13. 

  The SI unit of permeability in magnetic field is

  (a) Nm/A

  (b) Tm/A

  (c) Fm

  (d) N/Am

  None

  14. 

  The current in a wire flows from North to South in a horizontal plane. The direction of magnetic field at a point at distance r above the wire will be

  (a) towards south

  (b) towards east

  (c) towards west

  (d) towards north-east

  None

  15. 

  The magnetic field at the centre of a semicircular wire of radius r carrying current I clockwise is

  (a) μ₀ I / 2πr, perpendicular and out of the page of paper

  (b) μ₀ I / 2r, perpendicular and into the page of paper

  (c) μ₀ I / 4r, perpendicular and out of the page of paper

  (d) μ₀ I / 4r, perpendicular and into the page of paper

  None

  16. 

  The line integral of magnetic field around a closed loop is μ₀ times the current enclosed by the loop. This law is related with

  (a) Biot-sart’s law

  (b) Coulomb’s law

  (c) Gauss’s law in magnetostatics

  (d) Ampere Circuital law

  None

  17. 

  A sqare (each side a) loop carries current I anticlockwise having N turns. The magnitude and direction of dipole Moment is

  (a) a²NI, perpendicular outward, from South to North

  (b) a² N/I, perpendicular inwards, from South to North

  (c) NI/a², outwards from south to North

  (d) a²NI, perpendicular outward, from North to South

  None

  18. 

  When plane of the coil is parallel to magnetic field, the torque acting on the moving coil is

  (a) NIAB sin θ

  (b) NIAB

  (c) zero

  (d) NIAB cos θ

  None

  19. 

  The current sensitivity of a moving coil galvanometer can be increased by

  (a) increasing the number of turns only

  (b) increasing the magnetic field only

  (c) increasing the area of coil only

  (d) decreasing the torsional constant

  None

  20. 

  The voltage sensitivity of a moving coil galvanometer is the

  (a) product of current sensitivity and resistance of the coil

  (b) ratio of current sensitivity to the resistance

  (c) voltage per unit deflection

  (d) deflection per unit current

  None

  Previous Start Quiz Next
  

  Time’s up

Chapter-5: Magnetism and Matter

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-5-Magnetism and Matter

  1. 

  Curie temperature is the temperature above which

  (a) a ferromagnetic material becomes paramagnetic

  (b) a paramagnetic material becomes diamagnetic

  (c) a ferromagnetic material becomes diamagnetic

  (d) a paramagnetic material becomes ferromagnetic

  None

  2. 

  The relative permeabily of paramagnetic substance is

  (a) equal to 1

  (b) greater than 1

  (c) less than 1

  (d) much greater than 1

  None

  3. 

  The magnetic susceptibility of diamagnetic substance is -1.5. Its relative permeability is

  (a) 2.5

  (b) 0.5

  (c) -0.5

  (d) -1.5

  None

  4. 

  The ratio of Intensity of Magnetisation to the Magnetic field Intensity is called

  (a) Magnetic field intensity

  (b) Relative permeability

  (c) Magnetic Flux density

  (d) Magnetic susceptibility

  None

  5. 

  The SI unit of Magnetic field intensity is

  (a) Tesla

  (b) Henry

  (c) A/m

  (d) Oersted

  None

  6. 

  A bar magnet is cut into two half axially. If it has magnetic dipole moment M, then the new magnetic dipole moment of each part is

  (a) M

  (b) M/2

  (c) 2 M

  (d) 3 M

  None

  7. 

  A bar magnet ofdipole moment M is rotated in the uniform magnetic field Bfrom horizontal to unstable equilibrium, then work done is

  (a) MB

  (b) 2 MB

  (c) -MB

  (d) -2 MB

  None

  8. 

  The SI unit of pole strength is

  (a) Am

  (b) Am²

  (c) A/m

  (d) Gauss

  None

  9. 

  Identify the incorrect statement.

  (a) two magnetic field lines neverr cross each other

  (b) magnetic field lines do not form a closed loop

  (c) A bar magnetic behaves as a solenoid

  (d) Magnetic field lines originate fromnorth pole and terminate to south pole externally

  None

  10. 

  Ifa paramagnetic subtance suspended vertically is in uniform horizontal magnetic field, it will immediately becomes

  (a) perpendicular to the field

  (b) parallel to the field

  (c) will notdeflect

  (d) none of these

  None

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Chapter-6: Electromagnetic Induction

• Notes
• Formula Sheet
• MCQs Induction
  Welcome to your Class 12 Physics: Ch-6-Electromagnetic Induction

  1. 

  The current in a self – inductance L = 40 mH is to be increased uniformly from 1 A to 11 A in 4 milliseconds. The magnitude of emf induced in the inductor during the process is

  (a) 440 V

  (b) 100 V

  (c) 40 V

  (d) 0.4 V

  None

  2. 

  A 100 mH coil carries a current of 1 A. Energy stored in the form of magnetic field is

  (a) 0.1 J

  (b) 0.5 J

  (c) 0.05 J

  (d) 1 J

  None

  3. 

  A sqaure coil abcd is entering into the increasing cross magnetic field, the direction of induced current

  (a) does not change

  (b) will be clockwise

  (c) will be anticlock wise

  (d) will be zero

  None

  4. 

  Lenz's law is based on the principle of

  (a) conservation of energy

  (b) conservation of momentum

  (c) conservation of mass

  (d) conservation of angular momentum

  None

  5. 

  A magnetic of Noth pole is moving towards a stationary coil. What will be the direction of induced current in the coil?

  (a) Clockwise

  (b) anticlock-wise

  (c) No current will induce

  (d) none of these

  None

  6. 

  Case_1: A conductor is moving and magnetic field is stationary. Case-2: A conductor is stationary and magnetic field is moving. Answer the followings.

  (a) Case -1 is emf and Case-2 is motional emf

  (b) case-1 is motional emf and Case-2 is emf

  (c) Bothcases applied in emf

  (d0 both cases are applied for motional emf

  None

  7. 

  A conductor AB (A- bottom, B-Top) of length L is vertically placed in the dot magnetic field and conductor is moving with velocity vector v perpendicular to the length towrds right The polarity of B is

  (a) Positive

  (b) Negative

  (c) No parity

  (d) emf = 0

  None

  8. 

  A circular coil is placed to the right of an infinite wire in which current is increasing. The direction of inducced current in the circular coil is

  (a) anticlockwise

  (b) clockwise

  (c) zero

  (d) does not change

  None

  9. 

  The expression of induced emf in a coil of inductance L is

  (a) e + L dI/dt

  (b) e = -L dI/dt

  (c) e = dI/dt

  (d) e = L

  None

  10. 

  The SI unit of self inductance is

  (a) Weber

  (b) Tesla

  (c) Henry

  (d) Weber-Ampere

  None

  11. 

  Self inductance ofa coil depends upon

  (a) Number turns and directly proportinal

  (b) square of number of turns and inversely proportional

  (c) square of number of turns and directly proportional

  (d) magnetic flux

  None

  12. 

  If a solenoid coil has self inductance L. If its number of turns is increased twice, it self inductance becomes

  (a) twice

  (b) four times

  (c) becomes half

  (d) becomes one-fourth

  None

  13. 

  The energy density inmagnetic field of a solenoid is directly proportinal to

  (a) Magnetic field

  (b) directly proportional to sqaure of magnetic field

  (c) inversely proportional to magnetic field

  (d) inversely proportional to square of magnetic field

  None

  14. 

  If there is no relative motion between coil-1 (stationary) and coil-2 (moving towards coil-1, then

  (a) no emf induced in coil-1

  (b) emf will induce in coil-1

  (c) direction of induced current in coil -1 will be clockwise

  (d) None of these

  None

  15. 

  The current changes from 0 A to 2 A in time 1 ms in a coil of self inductance 0.04 H. The potential difference across the coil will be

  (a) 40 V

  (b) -40 V

  (c) 4 V

  (d) 80 V

  None

  16. 

  What is the energy stored in a solenoid of inductance 4 H and cirrent 2 A?

  (a) 4 J

  (b) 6 J

  (c) 8 J

  (d) 16 J

  None

  17. 

  A square coil of area 16 m² is placed in y-z plane. The magnetic field (B X 10⁻² T) makes an angle 60⁰ to the normal to the plane. The magnetic flux passes through it is

  (a) 0.16 B Wb

  (b) 0.08 B Wb

  (c) zero

  (d) 0.08√3 Wb

  None

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Chapter-7: Alternating Current

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-7- Alternating Current

  1. 

  The instantaneous voltage and current equation in a series L-C-R ac circuit is: V=200 sin⁡ (314t) (V) and i=10 sin⁡(314t- 60⁰), What is the nature of circuit and power factor?

  (a) Inductive, 0.866

  (b) Inductive, 0.5

  (c) Capacitive, 0.866

  (d) Capacitive, 0.6

  None

  2. 

  What is the the condition of resonance in LCR seies ac circuit?

  (a) Power factor zero

  (b) Power factor unity

  (c) Impedance maximum

  (d) Average power minimum

  None

  3. 

  A transformer converts high voltage low current into low voltage high current. The transformer is

  (a) Step up transformer

  (b) Step down transformer

  (c) Core type

  (d) Shell type

  None

  4. 

  When the supply frequency is greater than resonant frequency, the LCR series ac circuit is

  (a) Inductive type

  (b) Capacitive type

  (c) Purely inductive

  (d) Purely capacitive

  None

  5. 

  When inductive reactance is equal to capacitive reactance, the LCR series ac circuit is

  (a) in resonance

  (b) not in resonance

  (c) capacitive circuit

  (d) inductive circuit

  None

  6. 

  The average power is maximum in a LCR series ac circuit, the circuit is

  (a) Inductive

  (b) capacitive

  (c) purely resistive

  (d) purely inductive

  None

  7. 

  In AC circuit, the wattless circuit in which average power is: (φ = phase difference between voltage and current)

  (a). VI sin φ

  (b). VI cos φ

  (c). VI

  (d). √(3) VI

  None

  8. 

  If voltage leads the current by 90⁰ in AC circuit, then the circuit is

  (a) Prely resistive

  (b) Purely capacitive

  (c) Purely inductive

  (d) LCR circuit

  None

  9. 

  In an ac circuit, the ratio of resonant angular frequency to the bandwith is known as

  (a) Power factor

  (b) Quality factor

  (c) Load factor

  (d) Capacitive factor

  None

  10. 

  In ac circuit, the instantaneous voltage and current equations are: V= V₀ sin (ωt + 30⁰) and i = I₀ cos ωt. The power facror of the circuit is

  (a) 1

  (b) 0.5

  (c) -0.5

  (d) 1.73

  None

  11. 

  The transformation ratio of a transformer having effiency is

  (a) Ns/Np = Vs/Vp = (efficiency X Ip)/Is

  (b) Ns/Np = Vs/Vp = (efficiency X Is)/Ip

  (c) Ns/Np = Vp/Vs = Is/Ip

  (d) None of the above

  None

  12. 

  Average power in an ac circuit is

  (a) VI cos φ

  (b) VI sin φ

  (c) VI

  (d) √(3) VI

  None

  13. 

  The wattless circuit is AC is/are

  (a) Purely resistive circuit

  (b) Purely Inductive circuit

  (c) Purely capacitive circuit

  (d) Prely inductive and Purely apacitive circuit

  None

  14. 

  If V = 220 sin (314 t +15⁰) (volt) and I = 11 sin (314 + 75⁰) (amp), find power factor and impedance of the circuit.

  (a) 0.5, 20 Ω

  (b) 0 and 20 Ω

  (c) 0.866 and 50 mΩ

  (d) 1 and 20 Ω

  None

  15. 

  If potential difference across L and C are 60 V ac and 50 V ac respectively. The voltage drop in R is 10 V ac, then the power factor and nature of LCR ac series circuit is

  (a) unity and inductive circuit

  (b) 0.707 and prely resistive circuit

  (c) unity and capacitive circuit

  (d) 0.707 and purely inductive circuit

  None

  16. 

  The shape of the graph between capacitive reactance and and frequency is

  (a) straight line

  (b) parabola

  (c) rectangular hyperbola

  (d) parallel to frequency axis

  None

  17. 

  A bulb is connected in series with an purely inductor across ac voltage. What will be the effect on brightness of the bulb if iron core is inserted in the inductor?

  (a) bulb will glow more bright.

  (b) bulb will glow dim.

  (c) bulb will be fused.

  (d) bulb will have same brightness.

  None

  18. 

  The average value of sin ωt over complete one cycle is

  (a) zero

  (b) 1/2

  (c) 1/√2

  (d) none of the these

  None

  19. 

  In LCR ac circuit, the potential difference across inductance is equal to the potential difference across C. The circuit will be

  (a) inductive

  (b) capacitive

  (c) in resonnce

  (d) rejector circuit

  None

  20. 

  A transformer is based on the principle of

  (a) Self induction

  (b) mutual induction

  (c) conservation of charge

  (d) conservation of energy

  None

  21. 

  The losses in a transformer is/are

  (a) core loss only

  (b) copper loss only

  (c) friction and windage loss

  (d) both copper and core losses

  None

  22. 

  For the current I = I₀ sin (314 t), how many times the current will be zero?

  (a) one time

  (b) two times

  (c) three times

  (d) four times

  None

  23. 

  In ac frequency 50 c/s, a graph is plotted between current and time. What is the time taken to reach from zero to first positive peak?

  (a) 1 ms

  (b) 2 ms

  (c) 5 ms

  (d) 50 ms

  None

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Chapter-8: Electromagnetic Waves

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-8-Electromagnetic Wave

  1. 

  Which spectrum has the highest wavelength?

  Infrared Ray

  Gamma Ray

  Ultraviolet Ray

  Microwave

  None

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Chapter-9: Ray Optics

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-9-Ray Optics

  1. 

  Which mirror has magnification 0.25?

  (a) Convex mirror

  (b) Concave mirror

  (c) Both the above mirrors

  (d) Plain Mirror

  None

  2. 

  Where should an object be placed infron ofa mirror on the principal axis to get virtual image?

  (a) Between focus and centre of curvature

  (b) Between optical centre and focus

  (c) at centre of curvature

  (d) Beyond centre of curvature

  None

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Chapter-10: Wave Optics

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-10-Wave Optics

  1. 

  Identify the incorrect option.

  Wavefront is the locus of oaal points which receives the light from the source.

  Ray of light is the perpendicular on the wavefront.

  Wavefront always moves in the forward direction.

  When a plane wavefront falls on a cocave mirror, the refracted wavefront is diverging spherical wavefront.

  None

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Chapter-11: Dual Nature of Radiation and Matter

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-11-Dual nature of Radiation & Matter

  1. 

  For photoelectron emission,which one is the incorrect option?

  Energy of incident light (E) > Work function (W)

  Incident frequency (f) > Threshold frequency (f₀)

  Wavelength (λ) > Threshold wavelength (λ₀)

  Wavelength (λ) < Threshold wavelength (λ₀)

  None

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Chapter-12: Atoms

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-12-Atoms

  1. 

  The nth radius of an electron in hydrogen atom is: (n is orbital number)

  directly proportional to n

  inversely proportional to n

  directly proportional to n²

  inversely proportional to n²

  None

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Chapter-13: Nuclei

• Notes
• Formula Sheet
• MCQs
  Welcome to your Class 12 Physics: Ch-13-Nuclei

  1. 

  Two nuclei Aluminium and Sodium have different mass numbers. What is the ratio of their nuclear densities?

  1 : 2

  1 : 1

  2 : 1

  1 : 3

  None

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Chapter-14: Semiconductor and Electronic Devices

• Notes

• Formula Sheet

• MCQs
  Welcome to your Class 12 Physics: Ch-14-Semiconductor

  1. 

  Which option is incorrect?

  (a) When Aluminium is doped with pure Silicon, it becomes n-type semiconductor.

  (b) When Arsenic is added with pure Silicon, it becomes n-type semiconductor.

  (c) In forward bias, barrier height is reduced.

  (d) In p-type semiconductor, majority charge carries are holes.

  None

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