ANNA UNIVERSITY,CHENNAI

JUNE/JULY 2012 EXAMINATION

(common to all colleges over Tamilnadu)

REJINPAUL.COM IMPORTANT QUESTIONS

SUBJECT : PH2161/

**ENGINEERING PHYSICS II**-----------------------------------------------------------------

NOTE: THESE ARE ONLY IMPORTANT QUESTIONS FROM EXPERTS THESE QUESTIONS MAY OR MAY NOT BE ASKED FOR ANNA UNIVERSITY JUNE/JULY 2012 EXAMINATION.

THE CREATIVITY AND EDITION OF QUESTIONS BELONGS TO REJINPAUL.COM :PREM,ADMIN

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UNIT I

1. Starting from classical free electron theory of metals obtain an expression for electrical and thermal conductivites and hence prove wiedemann franz law

2. Explain the meaning of ‘density of states’. Derive an expression for the number of allowed states per unit volume of a solid

3. Derive an expression for Thermal conductivity and electrical conductivity on the basis of classical free electron theory

4. Write Fermi –Dirac distribution function. Explain how Fermi function varies with temperature.

UNIT II

1. Derive an expression for the concentration of electron in the conduction band of an intrinsic Semiconductor.

2. What is Hall Effect? Give the theory of Hall Effect and hence justify how Hall coefficient

depends on the doping concentration. Describe an experimental set up to determine the Hall Co efficient

3. Derive an expression for density of holes in the valance band of P type semiconductor.

4. What is an intrinsic semiconductor? Obtain a mathematical expression for the carrier concentration in intrinsic semiconductor. And the method of determining the band gap of a semiconductor

5. Derive an expression for carrier concentration and Fermi energy in a N –Type semiconductor

UNIT III

1. What are superconductors? Give two examples. Explain their properties,applications

2. How can hysterisis of ferromagnetic material be accounted based on domain theory. Write down the applications of ferrites in detail.

3. Distinguish between type I and type II superconductors. Explain any two applications of superconductors.

4. Write Short Notes on Josephson effect, Meissner effect, Isotope effect and SQUID

UNIT IV

1. Derive an expression for ionic and electronic polarization in dielectric material.

2. Derive an expression for local field in a dielectric material and hence deduce Clausius –Mosotti equation

3. Derive an expression for the local field in a dielectric for a cubic structure

4. What is dielectric polarization? Mention the different mechanisms of polarization in different dielectric materials.

5. What are the remedies to avoid breakdown mechanisms and Discuss the effect of frequency on polarization.

UNIT V

1. Discuss in detail about metallic glasses and what are the method of production , types, properties of the same

2. Discuss in detail about carbon Nano tubes and Elaborate properties and application

3. Explain the shape memory effect, pseudo elasticity and hysteresis property of shape memory alloys and discuss the application

4. Describe the pulsed laser deposition technique to synthesis Nano materials