# SET OF MUST PRACTICE QUESTIONS FOR CBSE PHYSICS CLASS XII (AISSCE PHYSICS 2011)

Hello Dear Students, If you were searching for a set of questions which you cannot afford to leave while preparing for AISSCE 2011 Physics Exam, Here it is. Please practice them carefully. If you have any doubt in answering any of these questions, please feel free to ask at www.askphysics.com The content is being updated by adding more questions daily. So please come back soon for more

ELECTROSTATICS

1. State Coulomb’s law and express it in vector form
2. Derive an expression for the electric field due to a dipole at a point on its
1. axial position and
2. on the equatorial position.
3. State Gauss theorem of electrostatics and use it to find the electric field at a point due to
1. A point charge
2. A line of charge
3. A plane sheet of charge
4. A sphere of charge
4. Derive Coulomb’s law from Gauss theorem
5. Derive an expression for the torques on a dipole in a uniform electric field
6. Derive an expression for the work done in rotating a dipole in a uniform electric field
7. Derive an expression for t6he potential energy of a dipole in a unifor electric field
8. Derive an expression for the potential energy of a system of point charges
9. Describe the principle of a parallel plate capacitor
10. Derive an expression for the capacitance of a parallel plate capacitor.
11. Derive an expression for the effective capacitance when capacitors are connected in (a) parallel (b) series
12. Derive an expression for the energy stored in a parallel plate capacitor
13. Derive an expression for the electric potential due to (a) a point charge (b) a system of point charges
14. Describe the principle construction and working of Van de Graff generator

CURRENT ELECTRICITY

1. State Ohm’s law
2. Define drift velocity and derive an expression for it.
3. Derive the relation I = nAev
4. Deduce Ohm’s law
5. Explain why the resistance of a conductor increases with increase in temperature.
6. Derive expression for the effective resistance when three resistors are connected in (a) series (b) parallel
7. State Kirchhoff laws
8. What is a Wheatstone’s bridge? State its principle and deduce it using Kirchhoff laws.
9. Explain how a metre bridge is used to determine the resistance of a given wire.
10. State and explain the Principle of a potentiometer and describe the experiment to determine the internal resistance of a primary cell using potentiometer.
11. Describe how a potentiometer is used to compare the emfs of two primary cells.

To be updated soon

MAGNETIC EFFECTS OF CURRENT

1. State Biot Savart law and apply it to determine the strength of magnetic field at a point on the axis of a circular coil carrying current
2. State Ampere’s circuital law and apply it to find the magnetic field inside a solenoid and a toroid.
3. Describe the principle construction and working of a cyclotron. Why a cyclotron cannot be used to accelerate electrons
4. Derive an expression for cyclotron frequency
5. Explain the principle construction and working of a moving coil galvanometer.
6. Define the terms figure of merit and sensitivity of a galvanometer.
7. Describe how will you convert a galvanometer into (a) ammeter (b) voltmeter

To be updated soon

ELECTROMAGNETIC INDUCTION AND AC

ELECTROMAGNETIC WAVES

1. Describe Hertz experiment to produce em waves
2. Write the properties of em waves
3. What is em spectrum? Write any 5 constituents of em spectrum in the order of increasing wavelength. Write two uses of each
4. Write Maxwell’s equations.
5. Discuss the inconsistency of Ampere’s circuital law and how it is removed in Ampere – Maxwell law.
6. What is displacement current?
7. Explain how em waves are produced?
8. Describe the transverse nature of em waves. (Show that em waves are transverse in nature)

OPTICS

DUAL NATURE OF MATTER AND RADIATIONS

ATOMS AND NUCLEI

ELECTRONIC DEVICES

COMMUNICATION SYSTEMS

One mark questions

1. What is the meant by the term attenuation ?

2. Why ground wave transmission is restricted to 1500 kHz?

3. Define critical frequency in sky wave propagation.

4. What type of modulation is required in TV transmission?

5. Why AM radio reception is affected by electrical disturbances while FM radio reception is not?

6. What should be the length of a dipole antenna for a carrier wave of frequency 3 x 108 Hz

7. Draw a block diagram showing the basic communication system.

8. What is the range of frequencies used for FM radio transmission?

Two marks Questions

1. Distinguish analog and digital transmission

2. Write the functions of transducer and repeater in Communication systems. 3. Distinguish amplitude modulation and frequency modulation.

4. Draw a block diagram showing a simple amplitude modulator

5. Explain how a message signal is extracted from Amplitude Modulated signal.

6. Distinguish Sky wave propagation and Space wave propagation.

7. Name the different layers of earth’s atmosphere.

8. Mention two ways in which the range of transmission can be increased.

9. Explain the term modulation index and describe its significance.

10. List four devices used for communication each of which differ from other in the mode of communication.

Three marks questions

1. Explain the need for modulation

2. Derive an expression for the range of transmission from an antenna of height h.

3. Describe the demodulation of AM wave using waveforms and circuit diagrams.