B.E-B.E Electrical and Electronics Engineering 2nd Sem PH 1151- PHYSICS-II(Anna University Chennai-2013)

                     B.E/B.TECH. DEGREE EXAMINATION, MAY/JUNE 2013

                                        Second Semester

                           Electrical and Electronics Engineering

                                  PH 1151- PHYSICS-II

                                    (Regulation 2008)

 

 

PART A-(10*2=20 marks)

1.Define density of states.

2.What is effective mass of an electrode and hole?

3.What is Fermi energy? Where it lies for intrinsic semiconductors?

4.Write any four applications of squids.

5.Define Bohr magneton and give the value of one Bohr magneton.

6.What is bubble memory?

7.What is dielectric loss and loss angle?

8.What are excitons and traps?

9.What are nano phase materials? Give any preparative methods.

10.What are solitons? Mention any two of its applications.

 

 

PART B-(5*16=80 marks)

11. (a) Derive an expression for electrical and thermal conductivity of metals and hence deduce Wiedeman- Franz law.

Or

(b) Derive an expression for density of states using this calculate carrier concentration of Metals in terms of Fermi energy.

 

12. (a) Derive an expression for density of electrons in the conduction band of n-type semiconductors. 

Or

(b) What is Hall effect? Derive an expression for the Hall co-efficient and Hall voltage and how will you determine them experimentally? Discuss its application in magnetic levitation.

 

13. (a) What is Hysteresis? With an experimental setup how will you draw hysteresis curve and Explain it on the basis of domain theory? Using this distinguish between hard and soft Magnetic materials.

Or

(b) What are Ferrites? Discuss in detail its structure, applications and explain ferrite core memory.

 

14. (a) Derive Langevin-Debye equation for total polarisation in dielectrics.

Or

(b) What are ferro electric materials? Describe in detail their properties and applications and Explain how the heat energy is converted into electrical energy using ferro electric energy converter?

 

15. (a) What are shape memory alloys? Discuss in detail their properties and applications mention their advantages and disadvantages.

Or

(b) Give a detailed account on

(i) Bio- materials,

(ii) Non- linear materials,

(iii) IC packing materials,

(iv) Optical mixing 

Earning:  ₹ 8.50/-