Hall Ticket No Question Paper Code: AHS006
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech I/II Semester Supplementary Examinations July, 2017
Regulation: IA-R16
ENGINEERING PHYSICS
[Common for I Semester IT, ECE and
Time: 3 Hours Max Marks: 70
Answer ONE Question from each Unit
All Questions Carry Equal Marks
All parts of the question must be answered in one place only
UNIT I
1. Define the terms dipole moment and polarization. Discuss the different polarizations mechanisms
in dielectrics.
If a NaCl crystal is subjected to an electric field of 1000 V/m and the resulting polarization is
4:3 calculate the dielectric constant of NaCl.
2. What is internal field? Derive an equation for internal field in case of one dimensional array of
atoms in dielectric solids.
A silicon material is subjected to a magnetic field of strength 1000 A/m. If the magnetic susceptibility
of silicon is calculate its magnetization. Also evaluate the magnetic flux
density of the field inside the material.
UNIT II
3. Obtain an expression for energy density of radiation under equilibrium condition in terms of
Einstein coefficients.
Explain the three major engineering applications of laser.
4. Explain the construction of He-Ne laser with neat diagram.Discuss its working in detail with
energy level diagram.
Calculate the energy difference in eV between the two energy levels of Neon atoms of He-Ne laser
if the transition between these levels results in emission of light of wavelength 632.8 nm
UNIT III
5. What are nanomaterials? Explain their electrical and magnetic properties.
Explain briefly quantum confinement nature of nano materials.
6. Explain qualitatively why nanomaterials are significantly different from bulk materials of the
same chemical composition.
Explain briefly chemical vapour deposition method of fabrication of nano materials with neat
sketch.
Page 1 of 2
UNIT IV
7. What are the properties of wave functions? Obtain the expression energy Eigen values an energy
functions for a practice in one dimensional potential well of infinite height.
What are matter waves? Derive the expression for de-Broglie wavelength.
8. Describe Davisson and Germer experiment to verify matter waves.
An electron is bond in one dimensional potential well of width 0.12 nm. Find the energy values
in the ground state and also the first two excited state in eV.
UNIT V
9. Define Fermi level in case of semiconductors and mention its position in intrinsic and extrinsic
semiconductors at 0 K.
The effective density of states for electrons and holes in silicon at 300 K are: 2:8
and 1:04 respectively. The energy gap is 1.1 eV. Calculate the intrinsic carrier
concentration at 450 K.
10. State and explain Hall effect and derive the expression for Hall coefficient.
A silicon plate of thickness 1mm, breadth 10mm and length 100mm is placed in a magnetic
field of 0:5wb/m2 acting perpendicular to its thickness. If A current flows along its length,
calculate Hall voltage developed if Hall coefficient is 3:66 10􀀀4m3/coulomb.