2010 Jawaharlal Nehru Technological University, Hyderabad Code No: 09A1BS02 R09 Set No. 4 I B.Tech Regular Examinations,June 2010 ENGINEERING PHYSICS Question paper
Code No: 09A1BS02 R09 Set No. 4
I B.Tech Regular Examinations,June 2010
ENGINEERING PHYSICS
Common to CE, ME, CHEM, BME, IT, MECT, MEP, AE, BT, AME, ICE,
E.COMP.E, MMT, ETM, EIE, CSE, ECE, EEE
Time: 3 hours Max Marks: 75
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) Obtain an expression for Fermi energy at T > 0 K.
(b) Derive an expression for density of states of electrons.
(c) Write short notes on:
i. De Broglie wavelength and
ii. Heisenberg's uncertainty principle. [4+7+4]
2. (a) Derive Bragg's law of crystal di raction.
(b) Describe, in detail, Debye-Scherrer method for the determination of crystal
parameter.
(c) A certain crystal re
ects monochromatic X-rays strongly when Bragg's angle
is 210 for the second order di raction. Calculate the glancing angle for third
order spectrum. [4+7+4]
3. (a) What is bonding in solids? Write the list of di erent types of bonding in
solids.
(b) Describe with suitable examples, the formation of covalent and Vander-Waal's
bonds in solids.
(c) What is bonding energy of a molecule? Explain. [4+7+4]
4. (a) Describe the top-down methods by which nanomaterials are fabricated.
(b) Explain how X-ray di raction can be used to characterize nanoparticles.[9+6]
5. (a) Discuss the propagation mechanism of light waves in optical bers.
(b) Derive the expression for the numerical aperture of an optical ber.
(c) A step index ber has a numerical aperture of 0.16, and core refractive index
of 1.45. Calculate the acceptance angle of the ber and the refractive index
of the cladding. [5+6+4]
6. (a) Using Kronig-Penney model show that the energy spectrum of an electron
contains a number of allowed energy bands separated by forbidden bands.
(b) De ne e ective mass of an electron. Explain its physical signi cance. [9+6]
7. (a) Show that the application of forward bias voltage across p-n junction causes
an exponential increase in number of charge carriers in opposite regions.
(b) Write notes on \Liquid Crystal Display".
(c) The current in a p-n junction at 270C, is 0.18 A when a large reverse bias
voltage is applied. Calculate the current when a forward bias of 0.98 V is
applied. [7+4+4]
8. (a) De ne the terms magnetic induction (B), magnetization (M) and magnetic
eld (H). Obtain an expression relating to these quantities.
(b) What are ferrites? Prove that ferrites are superior to ferro-magnetic materils.
Write the applications of ferrites.
(c) The magnetic susceptibility of aluminum is 2.3 10??5. Find its permeability
and relative permeability. [6+5+4]
KEYWORDS:ENGINEERING PHYSICS,ENGINEERING PHYSICS QUESTION PAPER,JNTU,JNTU QUESTION PAPER,JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD MCA-IV SEMESTER SUPPLEMENTARY EXAMINATIONS JUNE ENGINEERING PHYSICS
Code No: 09A1BS02 R09 Set No. 4
I B.Tech Regular Examinations,June 2010
ENGINEERING PHYSICS
Common to CE, ME, CHEM, BME, IT, MECT, MEP, AE, BT, AME, ICE,
E.COMP.E, MMT, ETM, EIE, CSE, ECE, EEE
Time: 3 hours Max Marks: 75
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) Obtain an expression for Fermi energy at T > 0 K.
(b) Derive an expression for density of states of electrons.
(c) Write short notes on:
i. De Broglie wavelength and
ii. Heisenberg's uncertainty principle. [4+7+4]
2. (a) Derive Bragg's law of crystal di raction.
(b) Describe, in detail, Debye-Scherrer method for the determination of crystal
parameter.
(c) A certain crystal re
ects monochromatic X-rays strongly when Bragg's angle
is 210 for the second order di raction. Calculate the glancing angle for third
order spectrum. [4+7+4]
3. (a) What is bonding in solids? Write the list of di erent types of bonding in
solids.
(b) Describe with suitable examples, the formation of covalent and Vander-Waal's
bonds in solids.
(c) What is bonding energy of a molecule? Explain. [4+7+4]
4. (a) Describe the top-down methods by which nanomaterials are fabricated.
(b) Explain how X-ray di raction can be used to characterize nanoparticles.[9+6]
5. (a) Discuss the propagation mechanism of light waves in optical bers.
(b) Derive the expression for the numerical aperture of an optical ber.
(c) A step index ber has a numerical aperture of 0.16, and core refractive index
of 1.45. Calculate the acceptance angle of the ber and the refractive index
of the cladding. [5+6+4]
6. (a) Using Kronig-Penney model show that the energy spectrum of an electron
contains a number of allowed energy bands separated by forbidden bands.
(b) De ne e ective mass of an electron. Explain its physical signi cance. [9+6]
7. (a) Show that the application of forward bias voltage across p-n junction causes
an exponential increase in number of charge carriers in opposite regions.
(b) Write notes on \Liquid Crystal Display".
(c) The current in a p-n junction at 270C, is 0.18 A when a large reverse bias
voltage is applied. Calculate the current when a forward bias of 0.98 V is
applied. [7+4+4]
8. (a) De ne the terms magnetic induction (B), magnetization (M) and magnetic
eld (H). Obtain an expression relating to these quantities.
(b) What are ferrites? Prove that ferrites are superior to ferro-magnetic materils.
Write the applications of ferrites.
(c) The magnetic susceptibility of aluminum is 2.3 10??5. Find its permeability
and relative permeability. [6+5+4]
KEYWORDS:ENGINEERING PHYSICS,ENGINEERING PHYSICS QUESTION PAPER,JNTU,JNTU QUESTION PAPER,JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD MCA-IV SEMESTER SUPPLEMENTARY EXAMINATIONS JUNE ENGINEERING PHYSICS