Anna university Physics previous Year Question Papers Download

Anna university Physics 1 previous Year Question Papers Download

B.E./B.Tech.Degree Examinations, November/December 2010

Regulations 2008

First Semester

Common to all branches

PH2111 Engineering Physics I

Time: Three Hours Maximum: 100 Marks

Answer ALL Questions

Part A - (10 x 2 = 20 Marks)

1. List down the disadvantages of piezoelectric e®ect.
2. Compare transmission and refection modes of non destructive testing using ultra-sonics.
3. Why is population inversion necessary to achieve lasing?
4. How i s electrons and holes confnement made in the active region of heterojunctionlaser?
5. What are the different types of classifcation of optical fbres?
6. Explain dispersion in an optical fiber.
7. Defne blackbody and blackbody radiation.
8. What i s meant by wave function?
9. An element has a HCP structure. If the radius of the atom is 1.605ºA, find the height of unit cell.
10. What i s meant by a `Schottky pair'?


Part B - (5 x 16 = 80 Marks)
11. (a) With a neat diagram explain the method of production of ultrasound using
piezoelectric crystal. (16)
OR
11. (b) (i) With a neat diagram, discuss the principle and inspection method of ul-
trasonic °aw detector. (12)
(ii) Calculate the velocity of ultrasonic waves in water using acoustic grat-
ing. The frequency of the ultrasonic wave generated by transducer is 2
MHz. The di®raction angle measured is 8'45" in the third order di®rac-
tion pattern. Wavelength of laser light used in this experiment is 6328A. º
(4)
12. (a) Discuss the Einstein's theory of stimulated absorption, spontaneous and stim-
ulated emission of radiation. What are the conditions for light amplifcation?
(16)
OR
12. (b) (i) What is hologram? What are the necessary steps involved in recording
and reconstruction of a hologram? (12)
(ii) Compare holography with photography. (4)
13. (a) (i) Explain the basic structure of an optical fibre and discuss the principle of
transmission of light through optical fibres. (5)
(ii) Derive an expression for numerical aperture. (5)
(iii) Brie°y discuss a technique of optical fbre drawing. (6)

OR
13. (b) Explain the concept of optical ¯ber sensors and describe in detail about any
two sensors. (6 + 10)
14. (a) (i) What is meant by matter wave? (2)
(ii) Derive an expression for the wavelength of matter wave. (8)
(iii) Describe an experiment that veri¯es the existance of matter waves. (6)
OR
14. (b) Solve Schrodinger's wave equation for a particle in a box (one dimensional) and obtain the energy and eigen function. (16)
15. (a) (i) Defne atomic packing factor. (2)

(ii) Calculate the number of atoms, atomic radius, coordination number and atomic packing fraction for BCC and FCC structures. (10)
(iii) The distance between successive planes of Miller indices (111) is 2.078ºA
for a metal having FCC structure. Find the atomic radius and volume of
its unit cell. (4)
OR
15. (b) (i) Define the terms polymorphism and allotropy. (2)
(ii) Explain in detail the crystal defects and their types. (14)