Nalanda Open University
Annual Examination 2016
B.Sc. Physics (Honours), Part-III
Paper-VIII (Condensed Matter Physics Electronics)
Time: 3.00 Hrs. Full Marks: 80
Answer any five questions. All questions carry equal marks.
1. What is space lattice? Describe various types of lattices in the cubic system.
Show that for a simple cubic lattice, d100:d110:d111= 6 3 2
2. Discuss Van-der-waals binding. Obtain expression for the total potential
energy of pairs of atoms in the crystal on the basis of this theory.
3. Explain Drude-Lorentz theory. Derive Wiedmann-Franz relation between
thermal and electrical conductivities on the basis of this theory.
4. State and explain Thevenin's theorem. Giving an example show how this
theorem helps in circuit analysis.
5. Explain energy band. On the basis of energy bands of solids distinguish
between a metal, a semiconductor and an insulator.
6. What is photodiode? Discuss its working, characteristics and uses.
7. Whia is filter circuit? Give their classification and describe elementary filter
theory.
8. Explain the principle of frequency modulation. Define frequency deviation
and modulation index for a frequency modulated carrier.
9. What is an amplifier? Giving a neat circuit diagram discuss the working of
an R. C. Coupled amplifier. Explain Voltage gain.
10. Describe the face centred cubic and hexagonal closed packed crystal
structures. Prove that the close packing of atoms in the hcp structure
demands on axial ratio