D B4D394 Pages: 2

Reg. No. Name:
APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
FOURTH SEMESTER B.TECH DEGREE EXAMINATION, JUNE 2017

Course Code: EE206
Course Name: MATERIAL SCIENCE (EE)

Max. Marks: 100 Duration: 3 Hours

PART A
Answer all questions. Each question carries 5 marks.

1. Obtain the expression for the conductivity of an intrinsic semiconductor.
2. What are the common Dielectric materials used in Electrical apparatus.
3. Explain the term Electron Attachment.
4. What is the relevance of Curie — Weiss law?
5. What are organic solar cells?
6. Why certain materials exhibit superconductivity?
7. What is the scope of biomaterials in medicine?
8. Write notes on nano tubes
PART B
Answer any 2 questions. Each question carries 10 marks.

9. a. What is the effect of alloying of metals in their conduction? Illustrate with an

example. (6)
b. What is the effect of imperfections in lattice structure on the resistivity of pure
metals? (4)
10. a. What are the applications of thermoplastics and thermo setting plastics? (5)
b. Write notes on ferrites mentioning their properties and applications. (5)
11. a. Why SF6 gas is used in Circuit breakers? (5)
b. Which are the materials used in capacitor as insulatotors and why? (5)
PART C

Answer any 2 questions. Each question carries 10 marks.

12. Explain streamer theory of breakdown in air. (10)

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