CBSE +2 Physics

Class XII (Theory)
One Paper Time: 3 Hours 70 Marks
Unit I Electrostatics 08
Unit II Current Electricity 07
Unit III Magnetic effect of current & Magnetism 08
Unit IV Electromagnetic Induction and Alternating current 08
Unit V Electromagnetic Waves 03
Unit VI Optics 14
Unit VII Dual Nature of Matter 04
Unit VIII Atoms and Nuclei 06
Unit IX Electronic Devices 07
Unit X Communication Systems 05
Total 70

Unit I: Electrostatics (Periods 25)
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).
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 polarisation, 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. Van de Graaff generator.
Unit II: Current Electricity (Periods 22)
Electric current, flow of electric charges in a metallic conductor, drift velocity, mobility
and their relation with electric current; Ohm’s law, electrical resistance, V-I characteristics
(linear and non-linear), electrical energy and power, electrical resistivity and conductivity.
Carbon resistors, colour code for carbon resistors; series and parallel combinations of
resistors; 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 laws and simple applications. Wheatstone bridge, metre bridge.
Potentiometer - principle and its applications to measure potential difference and for
comparing emf of two cells; measurement of internal resistance of a cell.
Unit III: Magnetic Effects of Current and Magnetism (Periods 25)
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 and toroidal
solenoids.
Force on a moving charge in uniform magnetic and electric fields. Cyclotron.
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; moving coil galvanometer-its current sensitivity and
conversion to ammeter and voltmeter.
Current loop as a magnetic dipole and its magnetic dipole moment. Magnetic dipole moment
of a revolving electron. Magnetic field intensity due to a magnetic dipole (bar magnet)
along its axis and perpendicular to its axis. Torque on a magnetic dipole (bar magnet) in a
uniform magnetic field; bar magnet as an equivalent solenoid, magnetic field lines; Earth’s
magnetic field and magnetic elements. Para-, dia- and ferro - magnetic substances, with
examples. Electromagnets and factors affecting their strengths. Permanent magnets.
Unit IV: Electromagnetic Induction and Alternating Currents (Periods 20)
Electromagnetic induction; Faraday’s law, induced emf and current; Lenz’s Law, Eddy
currents. Self and mutual inductance.
Need for displacement current.
Alternating currents, peak and rms value of alternating current/voltage; reactance and
impedance; LC oscillations (qualitative treatment only), LCR series circuit, resonance;
power in AC circuits, wattless current.
AC generator and transformer.
Unit V: Electromagnetic waves (Periods 4)
Electromagnetic waves and their characteristics (qualitative ideas only). Transverse nature
of electromagnetic waves.
Electromagnetic spectrum (radio waves, microwaves, infrared, visible, ultraviolet, X-rays,
gamma rays) including elementary facts about their uses.
Unit VI: Optics (Periods 30)
Reflection of light, spherical mirrors, mirror formula. Refraction of light, total internal
reflection and its applications, optical fibres, refraction at spherical surfaces, lenses, thin
lens formula, lens-maker’s formula. Magnification, power of a lens, combination of thin
lenses in contact. Refraction and dispersion of light through a prism.
Scattering of light - blue colour of the sky and reddish appearance of the sun at sunrise
and sunset.
Optical instruments: Human eye, image formation and accommodation, correction of eye
defects (myopia, hypermetropia, presbyopia and astigmatism) using lenses. Microscopes
and astronomical telescopes (reflecting and refracting) and their magnifying powers.
Wave optics: wave front and Huygens’ principle, reflection and refraction of plane wave at
a plane surface using wave fronts. Proof of laws of reflection and refraction using Huygens’
principle. Interference, Young’s double slit experiment and expression for fringe width,
coherent sources and sustained interference of light. Diffraction due to a single slit, width of
central maximum. Resolving power of microscopes and astronomical telescopes. Polarisation,
plane polarised light; Brewster’s law, uses of plane polarised light and Polaroids.
Unit VII: Dual Nature of Matter and Radiation (Periods 8)
Dual nature of radiation. Photoelectric effect, Hertz and Lenard’s observations; Einstein’s
photoelectric equation-particle nature of light.
Matter waves-wave nature of particles, de Broglie relation. Davisson-Germer experiment.
Unit VIII: Atoms & Nuclei (Periods 18)
Alpha-particle scattering experiment; Rutherford’s model of atom; Bohr model, energy
levels, hydrogen spectrum.
Composition and size of nucleus, atomic masses, isotopes, isobars; isotones. Radioactivity-alpha,
beta and gamma particles/rays and their properties; radioactive decay law.
Mass-energy relation, mass defect; binding energy per nucleon and its variation with
mass number; nuclear fission and fusion.
Unit IX: Electronic Devices (Periods 18)
Semiconductors; semiconductor diode - I-V characteristics in forward and reverse bias,
diode as a rectifier; I-V characteristics of LED, photodiode, solar cell, and Zener diode;
Zener diode as a voltage regulator. Junction transistor, transistor action, characteristics of
a transistor; transistor as an amplifier (common emitter configuration) and oscillator. Logic
gates (OR, AND, NOT, NAND and NOR). Transistor as a switch.
Unit X: Communication Systems (Periods 10)
Elements of a communication system (block diagram only); bandwidth of signals (speech,
TV and digital data); bandwidth of transmission medium. Propagation of electromagnetic
waves in the atmosphere, sky and space wave propagation. Need for modulation.
Production and detection of an amplitude-modulated wave.
Practicals
Every student will perform 10 experiments (5 from each section) & 8 activities (4 from
each section) during the academic year. Two demonstration experiments must be performed by
the teacher with participation of students. The students will maintain a record of these
demonstration experiments.
B. Evaluation Scheme for Practical Examination:
þ One experiment from any one section 8 Marks
þ Two activities (one from each section) (4+4) 8 Marks
þ Practical record (experiments & activities) 6 Marks
þ Record of demonstration experiments & Viva based on these experiments 3 Marks
þ Viva on experiments & activities 5 Marks
Total 30 Marks

SECTION A
Experiments
1. To determine resistance per cm of a given wire by plotting a graph of potential
difference versus current.
2. To find resistance of a given wire using metre bridge and hence determine the specific
resistance of its material.
3. To verify the laws of combination (series/parallel) of resistances using a metre bridge.
4. To compare the emf of two given primary cells using potentiometer.
5. To determine the internal resistance of given primary cell using potentiometer.
6. To determine resistance of a galvanometer by half-deflection method and to find its
figure of merit.
7. To convert the given galvanometer (of known resistance and figure of merit) into an
ammeter and voltmeter of desired range and to verify the same.
8. To find the frequency of the a.c. mains with a sonometer.
Activities
1. To measure the resistance and impedance of an inductor with or without iron core.
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 circuit.
5. To study the variation in potential drop with length of a wire for a steady current.
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 diagram.
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 length.
2. To find the focal length of a convex lens by plotting graphs between u and v or
between l/u and l/v.
3. To find the focal length of a convex mirror, using a convex lens.
4. To find the focal length of a concave lens, using a convex lens.
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 microscope.
7. To find refractive index of a liquid by using (i) concave mirror, (ii) convex lens and
plane mirror.
8. To draw the I-V characteristic curve of a p-n junction in forward bias and reverse
bias.
9. To draw the characteristic curve of a zener diode and to determine its reverse break
down voltage.
10. To study the characteristics of a common - emitter npn or pnp transistor and to find
out the values of current and voltage gains.
Activities
1. To study effect of intensity of light (by varying distance of the source) on an L.D.R.
2. To identify a diode, an LED, a transistor, and IC, a resistor and a capacitor from
mixed collection of such items.
3. Use of multimeter to (i) identify base of transistor. (ii) distinguish between npn and
pnp type transistors. (iii) see the unidirectional flow of current in case of a diode
and an LED. (iv) check whether a given electronic component (e.g. diode, transistor
or I C) is in working order.
4. To observe refraction and lateral deviation of a beam of light incident obliquely on
a glass slab.
5. To observe polarization of light using two Polaroids.
6. To observe diffraction of light due to a thin slit.
7. To study the nature and size of the image formed by (i) convex lens (ii) concave
mirror, on a screen by using a candle and a screen (for different distances of the
candle from the lens/mirror).
8. To obtain a lens combination with the specified focal length by using two lenses
from the given set of lenses.