## CBSE Class 12 Physics Syllabus 2022-23

### THEORY

Time: 3 hrs. Max
Marks: 70

 No. of Periods Marks Unit–I Electrostatics 26 16 Chapter–1: Electric Charges and Fields Chapter–2: Electrostatic Potential and Capacitance Unit-II Current Electricity 18 Chapter–3: Current Electricity Unit-III Magnetic Effects of Current and Magnetism 25 17 Chapter–4: Moving Charges and Magnetism Chapter–5: Magnetism and Matter Unit-IV Electromagnetic Induction and Alternating Currents 24 Chapter–6: Electromagnetic Induction Chapter–7: Alternating Current Unit–V Electromagnetic Waves 04 18 Chapter–8: Electromagnetic Waves Unit–VI Optics 30 Chapter–9: Ray Optics and Optical Instruments Chapter–10: Wave Optics Unit–VII Dual Nature of Radiation and Matter 8 12 Chapter–11: Dual Nature of Radiation and Matter Unit–VIII Atoms and Nuclei 15 Chapter–12: Atoms Chapter–13: Nuclei Unit–IX Electronic Devices 10 7 Chapter–14: Semiconductor                                       Electronics: Materials, Devices and Simple Circuits Total 160 70

#### Unit I: Electrostatics – 26 Periods

Chapter–1: Electric Charges and Fields

Electric charges, Conservation of charge, Coulomb’s law-force between two- point charges, forces between multiple charges; superposition principle and continuous charge distribution.

Electric field, electric field due to a point charge, electric field lines, electric dipole, electric field due to a dipole, torque on a dipole in uniform electric field.

Electric flux, statement of Gauss’s theorem and its applications to find field due to infinitely long straight wire, uniformly charged infinite plane sheet and uniformly charged thin spherical shell (field inside and outside).

Chapter–2: Electrostatic Potential and Capacitance

Electric potential, potential difference, electric potential due to a point charge, a dipole and system of charges; equipotential surfaces, electrical potential energy of a system of two-point charges and of electric dipole in an electrostatic field.

Conductors and insulators, free charges and bound charges inside a conductor. Dielectrics and electric polarization, capacitors and capacitance, combination of capacitors in series and in parallel, capacitance of a parallel plate capacitor with and without dielectric medium between the plates, energy stored in a capacitor (no derivation, formulae only).

#### Unit II: Current Electricity – 18 Periods

Chapter–3: Current Electricity

Electric current, flow of electric charges in a metallic conductor, drift velocity, mobility and their relation with electric current; Ohm’s law, V-I characteristics (linear and non-linear), electrical energy and power, electrical resistivity and conductivity, temperature dependence of resistance, Internal resistance of a cell, potential difference and emf of a cell, combination of cells in series and in parallel, Kirchhoff’s rules, Wheatstone bridge.

#### Unit III: Magnetic Effects of Current and Magnetism – 25 Periods

Chapter–4: Moving Charges and Magnetism

Concept of magnetic field, Oersted’s experiment.

Biot – Savart law and its application to current carrying circular loop.

Ampere’s law and its applications to infinitely long straight wire. Straight solenoid (only qualitative treatment), force on a moving charge in uniform magnetic and electric fields.

Force on a current-carrying conductor in a uniform magnetic field, force between two parallel current-carrying conductors-definition of ampere, torque experienced by a current loop in uniform magnetic field; Current loop as a magnetic dipole and its magnetic dipole moment, moving coil galvanometer- its current sensitivity and conversion to ammeter and voltmeter.

Chapter–5: Magnetism and Matter

Bar magnet, bar magnet as an equivalent solenoid (qualitative treatment only), magnetic field intensity due to a magnetic dipole (bar magnet) along its axis and perpendicular to its axis (qualitative treatment only), torque on a magnetic dipole (bar magnet) in a uniform magnetic field (qualitative treatment only), magnetic field lines.

Magnetic properties of materials- Para-, dia- and ferro – magnetic substances with examples, Magnetization of materials, effect of temperature on magnetic properties.

#### Unit IV:   Electromagnetic Induction and Alternating Currents – 24 Periods

Chapter–6: Electromagnetic Induction

Electromagnetic induction; Faraday’s laws, induced EMF and current; Lenz’s Law, Self and mutual induction.

Chapter–7: Alternating Current

Alternating currents, peak and RMS value of alternating current/voltage; reactance and impedance; LCR series circuit (phasors only), resonance, power in AC circuits, power factor, wattless current.

AC generator, Transformer.

#### Unit V: Electromagnetic waves  – 04 Periods

Chapter–8: Electromagnetic Waves

Basic    idea    of    displacement    current,            Electromagnetic                waves,    their characteristics, their transverse nature (qualitative idea only).

Electromagnetic spectrum (radio    waves, microwaves, infrared, visible, ultraviolet, X-rays, gamma rays) including elementary facts about their uses.

#### Unit VI: Optics – 30 Periods

Chapter–9: Ray Optics and Optical Instruments

Ray Optics: Reflection of light, spherical mirrors, mirror formula, refraction of light, total internal reflection and optical fibers, refraction at spherical surfaces, lenses, thin lens formula, lens maker’s formula, magnification, power of a lens, combination of thin lenses in contact, refraction of light through a prism.

Optical instruments: Microscopes and astronomical telescopes (reflecting and refracting) and their magnifying powers.

Chapter–10: Wave Optics

Wave optics: Wave front and Huygen’s principle, reflection and refraction of plane wave at a plane surface using wave fronts. Proof of laws of reflection and refraction using Huygen’s principle. Interference, Young’s double slit experiment and expression for fringe width (No derivation final expression only), coherent sources and sustained interference of light, diffraction due to a single slit, width of central maxima (qualitative treatment only).

#### Unit VII:   Dual Nature of Radiation and Matter – 08 Periods

Chapter–11: Dual Nature of Radiation and Matter

Dual   nature   of   radiation,   Photoelectric   effect,   Hertz   and Lenard’s observations; Einstein’s photoelectric equation-particle nature of light.

Experimental study of photoelectric effect

Matter waves-wave nature of particles, de-Broglie relation.

#### Unit VIII:   Atoms and Nuclei – 15 Periods

Chapter–12: Atoms

Alpha-particle scattering experiment; Rutherford’s model of atom; Bohr model of hydrogen atom, Expression for radius of nth possible orbit, velocity and energy of electron in his orbit, of hydrogen line spectra (qualitative treatment only).

Chapter–13: Nuclei

Composition and size of nucleus, nuclear force

Mass-energy relation, mass defect; binding energy per nucleon and its variation with mass number; nuclear fission, nuclear fusion.

#### Unit IX:   Electronic Devices – 10 Periods

Chapter–14: Semiconductor Electronics: Materials, Devices and Simple Circuits

Energy bands in conductors, semiconductors and insulators (qualitative ideas only) Intrinsic and extrinsic semiconductors- p and n type, p-n junction

Semiconductor diode – I-V characteristics in forward and reverse bias, application of junction diode -diode as a rectifier.

#### PRACTICALS – Total Periods 60

The record to be submitted by the students at the time of their annual examination has to include:

Record of at least 8 Experiments [with 4 from each section], to be performed by the students.

Record of at least 6 Activities [with 3 each from section A and section B], to be performed by the students.

The Report of the project carried out by the students.

#### Evaluation Scheme

Max. Marks: 30
Time 3 hours

 Two experiments one from each section 7+7 Marks Practical record [experiments and activities] 5 Marks One activity from any section 3 Marks Investigatory Project 3 Marks Viva on experiments, activities and project 5 Marks Total 30 marks
##### SECTION–A

Experiments

1. To determine resistivity of two / three wires by plotting a graph for potential difference versus current.
2. To find resistance of a given wire / standard resistor using metre
3. To verify the laws of combination (series) of resistances using a metre

OR

To verify the laws of combination (parallel) of resistances using a metre bridge.

1. To determine resistance of a galvanometer by half-deflection method and to find its figure of
2. To convert the given galvanometer (of known resistance and figure of merit) into a voltmeter of desired range and to verify the same.

OR

To convert the given galvanometer (of known resistance and figure of merit) into an ammeter of desired range and to verify the same.

1. To find the frequency of AC mains with a

Activities

1. To measure the resistance and impedance of an inductor with or without iron
2. To measure resistance, voltage (AC/DC), current (AC) and check continuity of a given circuit using multimeter.
3. To assemble a household circuit comprising three bulbs, three (on/off) switches, a fuse and a power source.
4. To assemble the components of a given electrical
5. To study the variation in potential drop with length of a wire for a steady
6. To draw the diagram of a given open circuit comprising at least a battery, resistor/rheostat, key, ammeter and voltmeter. Mark the components that are not connected in proper order and correct the circuit and also the circuit

##### SECTION-B

Experiments

1. To find the value of v for different values of u in case of a concave mirror and to find the focal
2. To find the focal length of a convex mirror, using a convex
3. To find the focal length of a convex lens by plotting graphs between u and v or between 1/u and 1/v.
4. To find the focal length of a concave lens, using a convex
5. To determine angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation.
6. To determine refractive index of a glass slab using a travelling
7. To find the refractive index of a liquid using convex lens and plane
8. To find the refractive index of a liquid using a concave mirror and a plane
9. To draw the I-V characteristic curve for a p-n junction diode in forward and reverse

Activities

1. To identify a diode, an LED, a resistor and a capacitor from a mixed collection of such items.
2. Use of multimeter to see the unidirectional flow of current in case of a diode and an LED and check whether a given electronic component (e.g., diode) is in working
3. To study effect of intensity of light (by varying distance of the source) on an
4. To observe refraction and lateral deviation of a beam of light incident obliquely on a glass
5. To observe diffraction of light due to a thin
6. To study the nature and size of the image formed by a (i) convex lens, or (ii) concave mirror, on a screen by using a candle and a screen (for different distances of the candle from the lens/mirror).
7. To obtain a lens combination with the specified focal length by using two lenses from the given set of lenses.

Suggested Investigatory Projects

1. To study various factors on which the internal resistance/EMF of a cell
2. To study the variations in current flowing in a circuit containing an LDR because of a variation in
• the power of the incandescent lamp, used to ‘illuminate’ the LDR (keeping all the lamps at a fixed distance).
• the distance of a incandescent lamp (of fixed power) used to ‘illuminate’ the
1. To find the refractive indices of (a) water (b) oil (transparent) using a plane mirror, an equiconvex lens (made from a glass of known refractive index) and an adjustable object
2. To investigate the relation between the ratio of (i) output and input voltage and (ii) number of turns in the secondary coil and primary coil of a self-designed transformer.
3. To investigate the dependence of the angle of deviation on the angle of incidence using a hollow prism filled one by one, with different transparent
4. To estimate the charge induced on each one of the two identical Styrofoam (or pith) balls suspended in a vertical plane by making use of Coulomb’s
5. To study the factor on which the self-inductance of a coil depends by observing the effect of this coil, when put in series with a resistor/(bulb) in a circuit fed up by an C. source of adjustable frequency.
6. To study the earth’s magnetic field using a compass needle -bar magnet by plotting magnetic field lines and tangent galvanometer.