# CBSE Physics Practical For Class 12 2021

### CBSE Physics Practical For Class 12

#### PRACTICALS                                                                                               Total Periods: 32

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 demonstrated by teacher

### Evaluation Scheme

Time Allowed: Three hours                                                                          Max. Marks: 30

 Two experiments one from each section 8+8 marks Practical record [experiments and activities] 7 marks Viva on experiments, and activities 7 marks Total 30 marks

SECTION–A

Experiments

1. To determine resistivity of two / three wires by plotting a graph for potential difference versus
2. To find resistance of a given wire / standard resistor using metre

OR

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

#### OR

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

1. To compare the EMF of two given primary cells using

OR

To determine the internal resistance of given primary cell using potentiometer.

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

#### 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
3. To assemble a household circuit comprising three bulbs, three (on/off) switches, a fuse and a power
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 focal length of a convex lens by plotting graphs between u and v or between 1/u and 1/v.
2. To find the focal length of a convex mirror, using a convex

OR

To find the focal length of a concave lens, using a convex lens.

1. To determine angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of
2. To determine refractive index of a glass slab using a travelling
3. To find refractive index of a liquid by using convex lens and plane
4. To draw the I-V characteristic curve for a p-n junction diode in forward bias and reverse bias.

### Activities

1. To identify a diode, an LED, a resistor and a capacitor from a mixed collection of such
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 order.
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 polarization of light using two
6. To observe diffraction of light due to a thin
7. To study the nature and size of the image formed by a (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

### Practical Examination for Visually Impaired Students of Classes XI and XII Evaluation Scheme

Time Allowed: Two hours                                                                      Max. Marks: 30

 Identification/Familiarity with the apparatus 5 marks Written test (based on given/prescribed practicals) 10 marks Practical Record 5 marks Viva 10 marks Total 30 marks

General Guidelines

• The practical examination will be of two hour
• A separate list of ten experiments is included
• The written examination in practicals for these students will be conducted at the time of practical examination of all other
• The written test will be of 30 minutes
• The question paper given to the students should be legibly typed. It should contain a total of 15 practical skill based very short answer type questions. A student would be required to answer any 10
• A writer may be allowed to such students as per CBSE examination
• All questions included in the question papers should be related to the listed practicals. Every question should require about two minutes to be
• These students are also required to maintain a practical file. A student is expected to record at least five of the listed experiments as per the specific instructions for each subject. These practicals should be duly checked and signed by the internal examiner.
• The format of writing any experiment in the practical file should include aim, apparatus required, simple theory, procedure, related practical skills, precautions
• Questions may be generated jointly by the external/internal examiners and used for assessment.
• The viva questions may include questions based on basic theory/principle/concept, apparatus/ materials/chemicals required, procedure, precautions, sources of erro

## Class XII

1. Items for Identification/ familiarity with the apparatus for assessment in practicals (All experiments)

Meter scale, general shape of the voltmeter/ammeter, battery/power supply, connecting wires, standard resistances, connecting wires, voltmeter/ammeter, meter bridge, screw gauge, jockey Galvanometer, Resistance Box, standard Resistance, connecting wires, Potentiometer, jockey, Galvanometer, Lechlanche cell, Daniell cell [simple distinction between the two vis-à-vis their outer (glass and copper) containers], rheostat connecting wires, Galvanometer, resistance box, Plug-in and tapping keys, connecting wires battery/power supply, Diode, Resistor (Wire-wound or carbon ones with two wires connected to two ends), capacitors (one or two types), Inductors, Simple electric/electronic bell, battery/power supply, Plug-in and tapping keys, Convex lens, concave lens, convex mirror, concave mirror, Core/hollow wooden cylinder, insulated wire, ferromagnetic rod, Transformer core, insulated wire.

### B.      List of Practicals

1. To determine the resistance per cm of a given wire by plotting a graph between voltage and
2. To verify the laws of combination (series/parallel combination) of resistances by Ohm’s
3. To find the resistance of a given wire / standard resistor using a meter
4. To compare the e.m.f of two given primary cells using a
5. To determine the resistance of a galvanometer by half deflection
6. To identify a resistor, capacitor, inductor and diode from a mixed collection of such
7. To observe the difference between
• a convex lens and a concave lens
• a convex mirror and a concave mirror and to estimate the likely difference between the power of two given convex /concave
8. To design an inductor coil and to know the effect of
• change in the number of turns
• Introduction of ferromagnetic material as its core material on the inductance of the
9. To design a (i) step up (ii) step down transformer on a given core and know the relation between its input and output

Note: The above practicals may be carried out in an experiential manner rather than recording observations.