# PH6151 Engineering Physics-I Nov Dec 2016 Important Questions

Important questions / expected questions for Nov Dec 2016 PH6151 Engineering Physics-I examinations conducting by Anna University Chennai
B.E./ B.Tech. DEGREE EXAMINATION Nov Dec 2016
01st Semester / First Semester / I Year
Common to ALL departments
PH6151 Engineering Physics-I
(Regulation 2013)
Nov Dec 2016 Important Questions

Important 16 Marks Questions with answers (All five units) are listed for PH6151 Engineering Physics-I Subject

1. Explain the No. of atoms, atomic radius, Co-ordination number and packing factor for SC, BCC and FCC structures. (16)
2. a) Describe FCC structure. Derive the details about no. of atoms, Co-ordination number, atomic radius and packing factor. ( 8)
b) Metallic iron changes from BCC to FCC at 910° C and corresponding atomic radii vary from 1.258 A to 1.292 A . Calculate the percentage volume change during this structural change. (4)
3. Explain HCP structure. Show that for an HCP structure c/a = √8 /√3 and hence calculate Packing Fraction for HCP structure. (4 + 12)
4. a) Explain vapour growth techniques for growing crystal. (10)
b) Explain slow cooling and slow evaporation techniques. (6)
5. Explain the two melt growth techniques.
i) Czochralski’s method
ii) Bridgman technique (8 + 8)
6. (i) How will you classify three types of elastic modulii. Explain with necessary diagrams. Write the relationship between three modulii of elasticity. (10+2)
(ii) A wire of length 10 m and diameter 2 mm elongates 0.2 mm when stretched by a weight of 0.55 kg. Calculate Young’s modulus of the material of the wire. (4)
7. Derive an expression for depression at the free end of a cantilever due to load. Describe an experiment to determine the Young’s modulus of the cantilever material using this expression. (16)
8. Derive an expression for rectilinear flow of heat along an uniform bar  (one dimensional flow of heat) . (16)
9. (i) Derive an expression for thermal conductivity of the material of a thick pipe through which a hot liquid is flowing. (12)
(ii) How are heat conduction and electrical conduction analogous to each other? (4)
10. (i) Draw stress - strain diagram and discuss the behavior of ductile material under loading. ( 8)
(ii) Explain the factors affecting the elasticity. (8)
11. Derive the expression for Planck’s quantum theory of radiation. (10)
Deduce Wien’s displacement law & Rayleigh-Jeans law from Planck’s quantum theory of radiation (6)
12. Derive the expression for de-Broglie wavelength for matter waves. Express the de-Broglie
Wavelength in terms of energy and voltage. (6 + 6 + 4)
13. Derive Schrodinger’s time independent wave equation. (16)
14. Derive an expression for energy levels of a particle enclosed in one- dimensional box of width
’a’ and infinite height. (16)
15. Explain the principle, construction, working and applications of Transmission Electron Microscope. Also mention its advantages and disadvantages. (16)
16. Obtain Sabine’s expression for reverberation in a hall. (16)
17. (i) Explain the various factors affecting the architectural acoustics of a building and their remedies. (12)
(ii) Derive the expression for absorption co-efficient. (4).
18.  What is magnetostriction effect? Explain how ultrasonic waves can be produced by magnetostriction oscillator. Also mention its advantages, disadvantages and applications. (16)
19. (i) What is piezo electric effect? Describe the production of ultrasonic waves by piezoelectric oscillator method. (12)
(ii) Discuss its advantages, disadvantages and applications of piezoelectric oscillator method. (4)
20. (i) What is sonogram? Describe the principle and working of sonogram with block diagram. (2+8)
(ii )Explain the medical applications of ulrasonics. (4)
21. (i) Derive an expression for Einstein’s coefficient of spontaneous and stimulated emissions. (12)
(ii) How laser light differ from ordinary light. (4)
22. Describe principle, construction and working of a Nd:YAG laser with neat diagram. Also mention its advantages, disadvantages and applications. (16)
23. With suitable diagram, explain how the laser action is achieved in homo junction and hetro junction lasers? (8+8)
24. (i) What is attenuation? Discuss the different mechanisms which are responsible for attenuation in the optical fiber. (10 )
(ii) Explain the bending losses in an optical fiber. (6)
25. (i) Describe the construction and working of medical endoscope and give its application in medical field. (8)
(ii) Distinguish between
(a) Single mode fibre and multi mode fibre (4)
(b) Step index and graded index fibre (4)