ENGINEERING PHYSICS 1 ANNA UNIVERSITY NOV/DEC 2011 QUESTION PAPER | FIRST SEMESTER QUESTION PAPER ENGINEERING PHYSICS 1

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2011.

Common to All B.E./ B.Tech.

First Semester

182101 — ENGINEERING PHYSICS – I

(Regulation 2010)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 ´ 2 = 20 marks)

1. What is called the cavitation effect of ultrasonic waves?
2. A SONAR system receives the echo after 1.5 s from signal-launch in sea water.
Find the depth of the sea if the ultrasonic velocity in sea water is l490m/s.
3. What is population inversion in laser systems?
4. Compare normal photography and holography.
5. Distinguish between step-indexed fibre and graded indexed fibre.
6. What is called splicing of optical fibre?
7. What are matter waves?
8. What is the physical significance of wave function of a matter wave?
9. Identify the crystal structures with the following lattice parameters :
(a) a=b=c: a= b= ¹ g 90°
(b) a=b ¹ c; a= b=90°, g=120°.
10. What is known as Burger’s vector of a dislocation?

PART B — (5 ´ 16 = 80 marks)

11. (a) (i) Explain the principle, construction and working of a
magnetostriction oscillator to produce ultrasonic waves. (10)
(ii) Discuss the industrial applications of ultrasonics. (6)
Or
(b) Explain, with necessary schematic diagrams, the different ultrasonic
scan modes. (16)
12. (a) Deduce Einstein’s rate equations and hence obtain expressions for the
famous A and B coefficients for a two level system. What are the
important outcomes of the theory? (12+4)
Or
(b) Explain the working of a Nd:YAG laser along with the energy level
scheme and schematic device diagram. (16)
13. (a) (i) Derive expressions for the numerical aperture and maximum
acceptance angle of an optical fibre. (10)
(ii) Explain the working of a fibre-optic communication system with
neat schematic diagram. (6)
Or
(b) (i) With a neat schematic diagram, explain the working of a fibre-optic
endoscope in medical field. (10)
(ii) What are active and passive sensors? Explain, with a neat diagram,
the working of any one passive sensor. (2+4)
14. (a) What is called the Compton effect? Discuss the theory and experimental
study of it. List the important outcomes of the results. (2+12+2)
Or
(b) Discuss the theory of particle-in-a-box problem in one-dimension and
explain the results. (16)
15. (a) (i) Outline the various steps of obtaining the Miller indices of crystal
planes. Also sketch (210) and (212) planes separately. (2+4)
(ii) Derive an expression for the inter-planar distance of a cubic crystal.
(10)
Or
(b) Deduce the atomic radii, number of atoms per unit cell and packing
factors of BCC and FCC crystals. (16)
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