Osmania University (OU) 2012-4th Year B.E Engineering Physics III Internal, 1/, Affiliated - Question Paper

DEPARTMENT OF PHYSICS Vt 8 E - m Internal Examination (For all branches)) for the year 2011-2012 Time; 1 hour    Max    20

Part-A

Answer all questions. (3 x2 sfi marks)

1,    Define the terms Fermi energy and Fermi function.

2,    Calculate the packing Fractions for SC, BCC and FCC crystals

3,    Calculate the Inter plansr spacing for (123) plane hi Cubic Crystal tetOce (a=2.5A*)

Part - B Answer any TWO

4.    a. What are advantages of thin films over bulk materials 2M b.Exptotn chemical vapour deposit method to prepare thin ftms? 5M

5.    a. Expalln the point defects In crystals 2M

b. Obtain the expression for the equilibrium electron concentration in Wr semiconductors    5M

6. Write short notes of the following 7M

a.    Nano materials

b.    Electron mlaoscope (TEM)