Model paper : 01

Model paper : 01

Time: 3hrs II PUC Physics-33 Max marks: 90

Instructions: 1. Numerical problems solved with out writing the relevant formula carry no marks

2. Answers with out relevant diagram/fig/circuit wherever necessary will not carry any marks.

__________________________________________________________________________________________

PART A

I Answer the following 10 x1 = 10

1. What is the maximum value of permissible refracting angle of the prism in terms of critical angle to get

emergent ray.

2. Draw the energy distribution curve for diffraction at single slit.

3. What is dichroism?

4. Why Michelsons method of determining velocity of light is called null method?

5. If F is the force acting on a point charge, A due to charge B then what is the force on B due to A.

6. Fourth band of a resistor is gold. What does it signify?

7. Define Q factor.

8. What is elastic scattering of light?

9. Write beta decay equation given by Pauli.

10. Write the symbol of npn transistor.

PART B

II Answer any 10 of the following. 10X2 = 20

11. Write the expression for dispersive power of the material of the prism in terms of

a) Refractive index b) deviation produced by different rays

12. Explain Planks quantum theory, write the expression for momentum of photon.

13. What is diffraction grating? How is it produced?

14. What are elliptically and circularly polarized light?

15. Write the expression for torque on a electric dipole placed in the electric field. When does is

maximum?

16. What are notes and loops in electrical network?

17. Find the magnetic field inside the long solenoid having 500 turns, length 0.5 m carrying a current of 1A.

18. Obtain the expression for motional Emf when conductor moves in a magnetic field.

19. Write a neat labeled diagram of ruby laser.

20. Who discovered x- ray? Mention one of its use.

21. Write the symbol and truth table for OR gate.

22. Mention the types of thermo tropic liquid crystal.

PART C

III Answer any one of the following. 1X5 = 5

23. What is normal shift? Derive the expression for the same.

24. What are coherent sources? Mention the conditions to get steady interference pattern. Write the conditions for constructive and destructive interference.

IV Answer any two of the following. 2X5 = 10

25. Define effective resistance of combination of resistances. Obtain expression for effective resistance when number of resistors in parallel.

26. Give the theory of suspended coil galvanometer. Mention any one draw back of the instrument.

27. Describe briefly the photo emissive and photo voltaic cell. Mention any two applications of photo cells.

VPP

V Answer any two of the following. 2X5 = 10

28. Write a note on atomic nucleus with special reference to size, mass, charge, density and spin.

29. State radio active decay law. Obtain the expression for number of atoms present after time t.

30. What is transistor? Explain the action of npn transistor.

VI Answer any three of the following. 3X5 = 15

31. Parallel beam of light is incident on a sphere of diameter 0.2 m and refractive index 1.5. Calculate position where it focuses.

32. ABC is a right angled triangle with AB = 0.2 m BC = 0.6 m and ABC = 90o. A metal sphere of radius 0.02 m is charged to potential of 90000 volts and is placed at B. Find the amount of work done in moving a charge of 1 coulomb from C to A.

33. A 50 ohm resistor, a 0.5 H inductor and 40 micro farad capacitor are connected in series to an AC source of 120 V- 50 Hz. Calculate phase angle b/w voltage and current. Also calculate power factor.

34. Calculate wave length of limiting lines of Balmar series. Given, wavelength of first member of Lyman series is 121.5 nm.

VII Answer any one of the following. 1X5 = 5

35. Describe an experiment to determine the thickness of paper by the formation of interference pattern of air wedge.

36. Describe an experiment to construct OR and AND logic gates using diode writing truth tables.

VIII Answer any one of the following 1X5 = 5

37. Following readings were taken in an experiment to determine temperature co-efficient of thermister. Calculate temperature co-efficient.

Temperature in degree C

Standard resistance

Balancing length

28

100 ohm

52 cm

31

100 ohm

45 cm

38. Using following data calculate the sensitivity of given pointer galvanometer.

Trial

r in ohm

Value of high resistance

Deflection in GM

1

0.2

10

26

2

0.2

15

22

3

0.2

20

20

Given resistance of galvanometer is 60 ohm.

PART D

XIII Answer any one of the fallowing 1X(4+4+2) = 10

39. a)A polarimeter tube of length 0.2m contains sugar solution of specific rotation 0.011rad m2 kg-1 rotates

the plane of vibration through 200 calculate mass of sugar dissolved in 100cc of water.

b) Explain the principle of capacitor.

c) Write the expression for angular position nth order diffraction maxima & minima.

40. a) A circular coil of 10 terns & of mean radius 0.1m carries a current of 1A if the plane of the coil is

parallel to the magnetic meridian calculate the magnitude of resultant magnetic field at the centre

b) Describe G.P Thomson experiment to demonstrate wave nature of electron using a neat labeled

diagram.

c) Mention any two uses of capacitors.

____________________________________________________________________________________

VPP