M.Sc. (Semester IV) (CBCS) Examination Nov/Dec-2018
Materials Science
ADVANCED TECHNIQUES OF MATERIALS CHARACTERIZATION
Time: 2½ Hours Max. Marks: 70
Instructions: Attempt five questions.
Q 1 and Q 2 are compulsory.
Attempt any three questions from Q. 3 to 7.
Q.1 Choose correct alternatives. 08
In biconvex lens such as the front lens of a binocular, if object is kept at a
distance equal to less than focal length
No image is formed
Virtual, magnified image is formed
Real, magnified image is formed
Real, de-magnified image is formed
If the eyepiece magnification on light microscope is x 10 and the
objective is x40, what is the overall magnification?
x10 x40
x400 x4
In Electron microscope, light source is replaced by a beam of a very fast
moving
Electron Neutron
Proton Photon
Electron microscope is much more powerful than
Light microscope Compound microscope
Simple microscope Stereo microscope
To record X-ray photoelectron spectra of a given material, typical
pressure required in a vacuum chamber is
10-3 Torr 10-4 Torr
10-6 Torr 10-10 Torr
X-ray photoelectron spectroscopy comprises of
Ejection of core shell electron as a result of interaction of X-ray with
matter.
Ejection of valence band electron as a results interaction of
electromagnetic radiation emitted during de-excitation of electron from
L shell to K shell.
Excitation of electron to higher energy state.
Ejection of photon as a result of elastic collision.
Energy of the IR region of electromagnetic spectra is
400 4000 cm-1 400 4000 Å
400 4000 eV 400 4000 Hz
Given substance is Raman active, if and only if,
There is net change in polarization
There is net change in electric dipole moment
There is net change in magnetic dipole moment
Sample is ultra-thin
Page 2 of 2
SLR-VN-393
State True or False 06
In an electron microscope, electrons have a shorter wavelength than
visible light and therefore will have a lower resolving power.
In atomic force microscopy image of laser beam impinged on the back
side of the cantilever is used get topographic information of the surface.
In SEM, image formation is governed by hooks law.
Compared with SEM, the AFM provides extraordinary topographical
contrast of the surfaces.
Two electrically neutral and non-magnetic bodies held at a distance of
few nanometers, electrostatic forces usually is the dominating force
between them.
X-rays can eject non-core electrons.
Q.2 Write a short note on:
Polarization light microscope 05
Image formation in SEM 05
Selective Area Electron Diffraction (SEAD) 04
Q.3 Name the major parts of an optical microscope and state their functions. 08
List the parameters that affect the resolution of optical microscopes. 06
Q.4 Explain basic working principle of X-ray photoelectron spectroscope with the
help of suitable example.
08
With the help of suitable example qualitative and quantitative analysis of
Auger electron spectrum.
06
Q.5 What is EPR condition? Explain in detail continuous wave EPR and EPR line
width.
10
Explain what are bright field and dark field images in TEM. How do they are
formed?
04
Q.6 Draw schematic of TEM and explain working of each part. 10
Explain the necessity of high resolution NMR spectrometer for solid samples,
if any
04
Q.7 What do you mean by surface? What are different probes used for surface
characterization? What is order of vacuum required to record the XPS spectra
and why?
10
What are secondary and backscattered electrons? What is their origin? Where
those are useful?