Q1. (a) What do you mean by polarization? Mention the different mechanism of polarization of a dielectric material.
(b) With the help of graph, explain the frequency dependence of different contributions to the polarizability of dielectrics.
(c) Estimate the shift of the electron cloud with respect to the nucleus in argon
(Z=18) atom, when a field 10 5 v/m is applied. The polarizability of argon is 1.8 x 10 -40
F.m
2
.
OR
Q1. (a) Derive the relationship between E, D and P vectors. What is the significance of each of these vectors?
(b) What are ferroelectric and piezoelectric behavior of solids, explain along with the application?
Q2. (a) Define hysteresis loop in magnetic material. Draw a hysteresis loop for a ferromagnetic material and indicate in it.
(i) Residual induction (B r
)
(ii) Saturation induction (B s
)
(iii) Coercive force (H c
)
(b) Explain the difference between hard and soft magnetic materials.
(c) Find the relative permeability of a ferromagnetic material, if field of strength 220
Amp/meter produces magnetization 3300 Amp/meter in it.
OR
Q2. (a) Explain magnetic flux density B, magnetic flux intensity H and magnetization M.
How are they related to one another?
(b) Give the classification of magnetic materials and explain their application.
(c) A magnetic material has a magnetizing force and the relative permeability of the material.
Q3. (a) Explain crystal growth and zone refining.
(b) Describe the degenerate an non-degenerate states of semiconductor.
(c) Explain electronic properties of semiconductor (any two).
(i) Si
(ii) Ge
(iii) Sic
OR
Q3. (a) On the basis of electron theory, explain with diagram, the difference between direct and indirect band gap of semiconductor.
(b) Differentiate between drift current and diffusion current in semiconductor. Also write equations for the total current in a semiconductor crystal and explain the various terms.
Q4. (a) Derive an expression for the electrical conductivity of metals. How is it affected by temperature and alloys?
(b) Explain the effect of magnetic field on a superconductor. Also give some applications of superconductors.

(c) Find the relaxation time of conduction electrons in a metal. Of resistivity 1.54 x
10
-8 ohm-m, if the metal has 5.8 x 10
283
conduction electron per m
3
.
OR
Q4. (a) Give properties, composition and applications of two conducting and two resistive materials.
(b) Derive an expression for resistivity of impure metals.
(c) explain in brief:
(i) Type-I and Type-II superconductors
(ii) Drawback of classical free electon theory of conductor.
Q5. (a) Give a classification of capacitors on the basis of dielectric material used.
(b) what are the different types of core commonly used in making of an inductor?
Give a brief account of each one along with applications.
(c)what do you mean by PCB? Explain the classification of PCB on the basis of its construction. Give some applications of PCB.
OR
Q5. Write short notes on: (any two):
(i) Single sided PCB and double sided PCB
(ii) Wire wound Resistor
(iii) Step involved to construct copper clad laminate plate
(iv) Advantages and limitations of surface mount devices (SMDS).