Master of Science II (Physics-Materials Science)
Examination: Oct/Nov 2016 Semester III (Old CGPA)
SLR No. Day
Date Time Subject Name Paper No. Seat No.
SLR SH-
551
Monday
21/11/2016
2:30 P.M
to
5:00 P.M
Elements of Materials
Science
C
XI
Instructions: Q.1 and Q.2 are compulsory.
Attempt any 3 questions from Q.3 to Q.7
All questions carry equal marks.
Total Marks: 70
Q.1 Choose the correct alternative given in the bracket. 08
Which of these historical works of art contain nanotechnology?
Lycurgus cup
Medieval stained glass window in churches
Demascus steel swords
All of the above
Single electron tunneling occurs in carbon nanotubes at very small.
Capacitance Resistance
Electric current Magnetic filed
Coulomb blacked means the electron transport is blocked at
Low current Low voltage
High current High voltage
In metallic state the conductivity of the nanotubes is about
107/cm2 108/cm2
109/cm2 1010/cm2
Magnetoresistace is phenomenon whereby the resistance of a materials is
change by application of a
AC magnetic filed DC magnetic filed
AC electric filed DC electric filed
How many oxygen atoms lined up in a row would fit in a one nanometer
space?
None; an oxygen atom is bigger than 1 nm
One
Seven
Seventy
For a collection of nanoparticles to be a conductive medium, the particles
must be in
Magnetic contact Electric contact
Resistive contact Capacitive contact
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The tunneling process is a quantum mechanical phenomenon where an
electron can pass through an electron barrier at
Larger than potential
energy
Smaller than potential energy
Larger than kinetic energy Smaller than kinetic energy
State true or false 06
The band gap energy separation between the top vacant level of valence
band and the nearest filled level in the conduction band.
True False
In the weak regime the particle radius is larger than the radius of the
electron-hole pair.
True False
When the radius of the particles is smaller than the orbital radius of the
electron-hole pair the motion of the electron and hole become
independent and exciton does not exist.
True False
The band gap of the nanoparticles is decreases as size of nanoparticles
decreases.
True False
The intensity of absorption in UV-Vis spectroscopy in increases as the
particles size is reduced.
True False
If the emission within 10-8 second of the excitation it is called
phosphorescence.
True False
Q.2 Write short notes on: 14
Insulators
Photoluminescence
Photodiodes
05
05
04
0
Q.3 Define the excitons? Derived the Lambert-Beer laws. 10
Defined colour centers? Enlist the optical properties of photonic materials 04
Q.4 Define cathodoluminescence? Enlist the applications of luminescence. 08
Explain the different characteristics of photoconducting materials. 06
Q.5 Explain the working of photodetector. 08
Enlist the applications of light emitting diodes (LEDs) 06
Q.6 Explain the nucleation and growth mechanisms during the synthesis on
nanoparticles.
10
Give the applications of ceramics ceramic nanostructures materials. 04
Q.7 Describe the general mechanism of polymerization of monomer. 10
Give the properties and uses of polyvinylchloride. 04
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