Unit 1: Electrostatics 18 Pds.
Frictional electricity, charges and their conservation,
Coulomb's law, electric field and potential due to a point
charge, dipole, its fields along the axis and perpendicular
to the axis, concept of dielectric and dielectric constant.
Statement of Gauss's theorem-its application to find field
due to an infinite plane sheet of charge and inside a hollow
conducting sphere. Conductors and insulators, electrostatic
induction. Force and torque experienced by a dipole in
uniform electric field. Presence of free charges and bound
charges inside a conductor. Capacitance, parallel plate
capacitor with air/dielectric medium between the plates,
series and parallel combinations of capacitors, energy of a
capacitor, Van de Graff generator.
Unit 2 : Current Electricity 17 Pds.
Electric current, Ohm's law, resistivity, resistance of
different materials, temperature dependence of resistance,
colour code of resistors, resistances in series and parallel,
Kirchoff's laws-illustration by simple applications, Wheatstone's
bridge and its application in metre bridge, principle
of potentiometer-its application for comparing e.m.f. of two
cells and determination of internal resistance of a cell.
Unit : 3 Thermal and Chemical Effects of Current 11 Pds.
Electric power, heating effect of current, Joule's law.
Chemical effect of current and Faraday's laws of
electrolysis. Cells- primary (Voltaic, Leclanche, Daniel)
and secondary (lead accumulator). Thermo-electricity-Seebeck
effect and its explanation.
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Unit 4: Magnetic Effect of Current 10 Pds.
Oersted's experiment, Biot-Savart's law, magnetic field due
to a straight wire and a circular loop. Magnetic field due
to solenoid (quantitative idea). Force on a moving charge in
a uniform magnetic field, cyclotron. Force on current
carrying conductor and torque on current loop in a magnetic
field, forces between two parallel current carrying
conductor-definition of ampere. Moving coil galvanometer and
its conversion into ammeter and voltmeter.
Unit 5: Magnetism 10 Pds.
Natural and man-made magnets, properties of a bar magnet,
current loop as a magnetic dipole, magnetic moment as a
torque on a magnetic dipole in a uniform magnetic field.
Lines of force in a magnetic field. Comparison of bar magnet
and solenoid. Earth's magnetic field and its source
(elementary idea). Tangent galvanometer, vibration
magnetometer. Para, dia and ferro-magnetic substances with
examples., Electromagnets and permanent magnets.
Unit 6: Electromagnetic Induction and Alternating Currents 18 pds.
Induced e.m.f., Faraday's law, Lenz's law, electromagnetic
induction, self and mutual inductance, alternating currents,
impedance and reactance, power in A.C., circuits with L, C
and R. series circuit (Phasor diagram), resonant circuit.
Electrical machines and devices-transformer, A. C. generator,
choke and starter.
Unit 7: Electromagnetic Waves (Qualitative Treatment) 7 Pds.
History of electromagnetic waves (Maxwell, Hertz, Bose,
Marconi). Electromagnetic spectrum (radio, micro-waves,
infra-red, optical, ultraviolet, X-rays, and gamma rays)
including elementary facts about their uses and propagation
properties of the atmosphere w.r.t. various parts of
electromagnetic spectrum, green house effect.
Unit 8: Wave Optics 10 Pds.
Wave front and Huygen's principle. Reflection and refraction
of plane wave at a plane surface. Interference-Young's
double slit experiment. Diffraction-diffraction due to a
single slit, linearly polarised light, use of polarised
light, use of polaroids. Doppler effect.
Unit 9: Ray Optics and Optical Instruments 17 Pds.
Sources of light, luminous intensity, luminous flux,
illuminance. Photometry-Bunsen's grease photometer.
Reflection of light- curved mirrors, mirror formulae.
Refraction of light, total internal reflection, spherical
lenses, lens formulae, lens maker's formula, magnification.
Refraction and dispersion- of light due to a prism,
spectrometer-its use for determination of refractive index
of the material of a prism. Spectra-absorption and emission.
Scattering of light in atmosphere, primary rainbow. Optical
Instruments-simple And compound microscopes, refracting
(Astronomial) and reflecting (Newtonian) telescopes-resolving
power and magnifying power.
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Unit 10: Electrons and Photons 10 Pds.
Electrical conduction in gases-description of the different
patterns observed with decreasing pressure. Production and
properties of cathode rays. Thomson's experiment for e/m of
electrons, charge of electron by Millikan's oil-drop experi-
ment. Particle nature of light, Einstein's photoelectric
equation, photocells.
Unit 11: Atoms, Molecules and Nuclei 15 Pds.
Alpha particle scattering experiment, size of nucleus-
Rutherford model, Bohr model, energy quantisation, hydrogen
spectrum, composition of nucleus, atomic masses.
Radioactivity - alpha, beta and gamma particles/rays and their
properties, radioactive decay. Mass-energy relation.
Binding energy and mass defect. Nuclear fission, controlled
and uncontrolled nuclear reactions, nuclear reactor. Nuclear
fusion.
Unit 12 : Solids and Semiconductor Devices 18 Pds.
Energy bands in solids, conductors, insulators and semi-
conductors, pn junction, diodes, solar cells, junction
transistor, diode as rectifier, transistor as an amplifier
and oscillator, logic gates and combination of gates-NAND and
NOR.
Unit 13: Universe 7 Pds.
The constituents of the universe; planets-elementary idea
about determination of their distances and masses. Stars-
brightness, magnitude scale, luminosity, surface temperature;
energy source of stars (concept only).
CLASS XII (Practicals)
One Practical Paper 3 hours 30 marks 72 Pds.
Minimum of 10 experiments (5 from each Section A and Section B), 7 activities (a minimum of 3 from each section) and one investigatory project are to be performed by each student during a session.
Two experiments 14 marks (7 marks each)
Records of one Investigation Project and viva 3+2=5 marks based on Project
Records of experiments and activities 3+3=6 marks
Viva on experiments and activities 3+2=5 marks
List of experiments
Note: Two experiments i.e. one from each section will be given in
Board's practical examination.
Section-A
1. To establish current-voltage relationship (Ohm's law)
for a given resistance using an ammeter and voltmeter and to
find out the unknown value of resistances.
2. To find an unknown resistance using Wheatstone's bridge
(metre bridge).
3. To verify the laws of combination (series/parallel) of
resistances using metre bridge/post office box.
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4. To determine the specific resistance of the material of
a wire using metre bridge/post office box.
5. To compare of the e.m.f.s. of two given primary cells
using a potentiometer.
6. To determine the internal resistance of a primary cell
using a potentiometer.
7. To determine the resistance of a galvanometer by half
deflection method and to find its figure of merit.
8. Given the resistance and figure of merit of a
galvanometer, convert it into an ammeter/voltmeter of desired
range and to verify the same.
9. To find the relationship between potential difference
across a capacitor and time during its charging and
discharging.
10. To find the frequency of the A.C. mains using a
sonometer.
11. To plot the combined magnetic field of the earth and a
bar magnet placed in a defined position and to find the
position of neutral points.
12. To determine the value of `H' using a tangent
galvanometer by measuring the value of current with the help
of an ammeter.
Section B
1. To find the value of v for different value of u in case
of concave mirror and find its focal length.
2. To find the focal length of a convex lens by plotting
of graphs between (i) u and v and (ii) 1/u and 1/v.
3. To find the focal length of convex mirror using. a
convex lens/spherometer.
4. To find the focal length of concave lens using a convex
lens.
5. To plot the graph showing the variation of the angle of
deviation with angle of incidence for a glass prism.
6. To determine the refractive index of the material of a
plano-convex lens using a spherometer.
7. To draw the characteristic curve in forward bias pn
junction and to determine the static and dynamic residance of
the given diode.
8. To draw the characteristics of a Zener diode and to
determine its reverse break down voltage.
9. To study the characteristics of a common emitter npn or
pnp transistor and to find out the values of current and
voltage gains.
10. to study AND, OR and NOT gates using diodes and
transistors.
11. To study NAND and NOR gates.
List of Activities
Section A
Note: Record of performance of activities is to be
maintained. However, activities will not be given for
performing in the Board's practical examinations.
1. To construct a parallel plate capacitor and to study
its behaviour towards D.C. (through a neon bulb).
2. To measure the resistance and impedance of an inductor
with and without iron core.
3. To multimeter for measuring resistances (carbon
resistors) and compare the measured values with those written
in colour code.
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4. To measure potential gradient along a wire with a
voltmeter, and to compare this value with multimeter.
5. To understand the difference between e.m.f. and RD. of
a cell (e.m.f. without load and RD. measured when cell is
connected to some load).
6. To study the effect of light on an LDR(light dependent
resistor).
7. To study the dependence of internal resistance of a
primary cell on any one of the following variables:
(i) distance between the electrodes.
(ii) common. area of electrodes.
(iii) nature of electrolyte.
8. To use a multimeter for
(i) continuity test of a cartridge fuse, a slide wire
bridge, and it potentiometer.
(ii) finding the D.C. voltages of different tappings on
an energised battery eliminator.
(iii) finding the output A.C. voltage of a step down
transformer (250-6V).
(iv) detecting the unidirectional flow of current
feature in case of a diode and an LED (light emitting
diode).
9. To identify a diode, a LED, a transistor, an IC, a
resistor and a capacitor from a mixed collection of such
items.
10. (a) To identify the base of the transistor and confirm
by using a multimeter (Note : The base lead may not be always
between the emitter and the collector).
(b) Also to find whether the given transistor is npn or pnp
type using a multimeter.
(Note: When use this way the common lead i.e.-ve or black
of the multimeter is to he taken as +ve).
Section B
1. To study refraction and lateral deviation of a ray of
light passing through a glass slab.
2. To study the variation of focal length in case of
convex lenses of same diameter with difference between centre
thickness and edge thickness.
3. To observe polarisation of light using polaroid pieces
(say used in front of digital panel of a calculator).
4. To study relationship between real and apparent depth
using a hollow slab (and water).
5. To analyse effect of nature of liquid on the focal
length of liquid lens formed on a concave mirror.
6. To study the nature and size of the image formed by a
concave mirror using candle and screen (for different
distances of the candle from the mirror).
7. To study the nature and size of the image formed by a
convex lens using a candle and screen (for different
distances of the candle from the lens).
8. To study the dependence of focal lengths of concave
mirrors on their curvatures.
9. To study dependence of angle of deviation on angle of
incidence for a glass prism (without plotting a graph).
Note: For detailed evaluation scheme, please refer to
marking-cum-scoring sheet for a specimen set of experiments
given in the booklet "Improving Science Practicals, Senior
Sec. Stage, Physics" published by CBSE and/or Guidelines for
Practical Paper in Physics included here in brief.
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Investigatory Projects
(Any one is to be submitted at the time of examination).
1. To study the various factors-of dependence of internal
resistance/emf/powers of different cells.
2. Investigate the different factors of dependence of the
electric resistance by studying different kinds of materials
(conductors, semi-conductors, insulators).
3. To study effectiveness of different materials for
insulation of heat.
4. To construct a time switch and study the dependence of
its time constant on various factors.
5. To study various factors affecting the focal length of
liquid lens.
6. To study the projected motion of a liquid jet under
various conditions.
7. To study the effectiveness of different detergents in
terms of quality and quantity.
8. To study infra-red radiation emitted by different
sources using photo-transistor.
9. To investigate the effect on the force of attraction
between a solenoid- and bar magnet when the current through
the solenoid is changed.
10. To study the luminosity of various electric lamps of
different makes and different powers.
11. To fabricate/assemble a refracting astronomical
telescope and study its resolution with different apertures
of objective lens.
Note: These are only specimens of Investigatory Projects. In
order to promote innovativeness, the students be encouraged to
take up new projects (other than the ones mentioned above) in
consultation with and the approval of the teacher concerned.
Many of the experiments demonstrated to support theory
teaching can be extended for project work.
GUIDELINES FOR PRACTICAL PAPER IN PHYSICS
1. Designing Practical Question Paper.
At present there is no pre-set question paper provided by the
CBSE for conducting practical examination. This flexibility has been
provided to give more freedom to the examiners for the improvement of
practical examination, keeping in view the resources and other
facilities available in laboratory of the school. However, detailed
instructions with regard to syllabus, distribution of marks and
conduct of practical examination have been provided. The internal
examiner and the external examiner together set the question papers
according to the prescribed curriculum and distribution of marks
already stated and for this purpose, the following major aspects are
worth considering:
(a) Validity-which can be improved by giving
appropriate weightage to different skills being tested,
coverage of various content areas and maintaining proper
difficulty level of the exercises.
(b) Reliability-which can be improved by increasing
the number of tasks by including number of short
exercises so as to test integrated skills aimed at
testing both processes of performance and product of
performances. Further, different sets of question
papers, should be comparable and be stated in simple,
concise and unambigous language.
(c) Usability-which can be improved by allotting
appropriate time and marks in accordance with nature,
purpose and scope of the test. Total time, total marks
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construction of practicals, their administration and
interpretations are the factors to be considered for
enhancing practicability of the practical test.
2. Development of Marking Scheme for Physics Practical Examination:
In the Board's examination, a student has to perform two
experiments i.e. one each from Section A and Section B. The
distribution of actual Maximum Marks of 30 over the different heads is
already stated. However, for better reliability in assessment and
also for convenience in scoring, the examiners may double the apparent
weightage to 60 marks. Consequently, the marks allotted under each
head will be doubled. The score so received should finally be reduced
to half by the examiners while submitting the marks-list and answer-
books to the Board.
Considering the apparent total weightage to be 60, the following
is a suggestive detailed distribution of marks for different aspects
of practicals in Physics. The exact value point-wise distribution of
marks will of course depend on the particular experiment set by the
examiners. However, it should be ascertained in the final recording
that the total marks are exactly equal to the allotted marks. Hence
care should be exercised to select actual marks for each aspect/value
point out of the range of marks suggested in the table. For further
clarification, CBSE publication on "Improving Science Practicals-
Physics" may be referred to.