PH 2111 ENGINEERING PHYSICS — I Previous year question paper r first year students Jan 2010 Civil Engineering

B.E./B.Tech. DEGREE EXAMINATION, JANUARY 2010

First Semester

Civil Engineering

PH 2111 — ENGINEERING PHYSICS — I

(Regulations 2008)

Time: Three hours Maximum: 100 Marks

Answer ALL Questions

PART A — (10 × 2 = 20 Marks)

1. What is cavitation?
2. What is sonogram?
3. What are different methods of achieving population inversion?
4. Distinguish between homojunction and heterojunction semiconductor lasers.
5. A signal of 100 mW is injected into a fibre. The outcoming signal from the
other end is 40 mW. Find the loss in dB?
6. What is meant by splicing in fibre optics?
7. Calculate the equivalent wavelength of electron moving with a velocity of
3 × 107 m/s.
8. What is Compton effect? Write an expression for the Compton wavelength.
9. For a cubic crystal draw the planes with Miller indices (110) and (001).
10. What are Frenkel and Schottky imperfections?
PART B — (5 × 16 = 80 Marks)
11. (a) (i) Explain how ultrasonic waves can be produced by using
magnetostriction method. (12)
(ii) Write any four applications of ultrasonic waves. (4)
Or
(b) In ultrasonic NDT what are the three different scan displays in common
use? Explain. (10 + 6)
12. (a) For atomic transitions, derive Einstein relations and hence deduce the
expressions for the ratio of spontaneous emission rate to the stimulated
emission rate.
Or
(b) What is holography? Describe the construction and reconstruction
methods of a hologram. (4 + 6 + 6)
13. (a) (i) How are fibres classified? Explain the classification in detail. (8)
(ii) Explain double crucible method of fibre manufacturing. (8)
Or
(b) (i) Explain the construction and working of displacement and
temperature fibre optic sensors. (5 + 5)
(ii) Explain the construction and working of fibre-optic medical
endoscope. (6)
14. (a) (i) Write a note on black body radiation. (4)
(ii) Derive Planck’s law of radiation. (12)
Or
(b) (i) What is the principle of electron microscopy? Compare it with
optical microscope. (4)
(ii) With schematic diagram explain the construction and working of
scanning electron microscope. (12)
15. (a) (i) Explain the terms: atomic radius, coordination number and packing
factor. (6)
(ii) Show that the packing factor for Face Centered Cubic and
Hexagonal Close Packed structures are equal. (10)
Or
(b) (i) What are Miller indices? Explain. (4)
(ii) Derive an expression for the interplanar spacing for (hkl) planes of
a cubic structure. (10)
(iii) Calculate the interplanar spacing for (101) plane in a simple cubic
crystal whose lattice constant is 0.42 nm. (2)