Hall Ticket No Question Paper Code: AHSB04
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
Four Year B.Tech I Semester End Examinations (Supplementary) January, 2019
Regulation: IARE R18
WAVES AND OPTICS
Time: 3 Hours (Common to AE ME ECE) 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. Considering dual nature of electron, Derive Schrodinger's time independent wave equation for
the motion of an electron.
An electron is accelerated by a potential difference of 150V. what is the wavelength of that
electron wave.
2. Using Planck's and Einstein's theory of radiation, Show that the wavelength associated with an
electron of mass and kinetic energy is given by p h
2mE
.
Calculate the minimum energy of an electron that can possess in an infinitely deep potential well
of width 4nm.
UNIT II
3. On the basis of band theory classify the solids into conductor, semiconductor and insulator.[7M]
Calculate Hall voltage developed across the width of the slab of a metallic slab carrying a current
of 30A is subjected to a magnetic field of 1.75T. The magnetic field is perpendicular to the plane
of the slab and to the current. The thickness of the slab is 0.35cm. The concentration of free
electrons in the metal is 6.55 x 1028electrons/m3. .
4. Describe an experimental setup for the measurement of hall voltage and give its applications.

Calculate the density of charge carriers of semiconductor, given the Hall coefficient is -6.85 ×
m3/Coulomb.
UNIT III
5. Explain the working of ruby laser with a neat diagram. Mention its advantages and disadvantages.

Calculate the wavelength of emitted radiation from a semiconductor diode laser, which has a
band gap of 1.44eV.
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6. With a neat diagram discuss principle and construction of optical fibre
An optical fibre has a core material of refractive index of 1.55 and cladding material of refractive
index of 1.50. The light is lunched into in air. Calculate its numerical aperture.
UNIT IV
7. State and explain Huygens principle with a neat diagram.
Two slits 0.125mm apart are illuminated by a light of wavelength 4500 A°. The screen is 1m
away, from the plane of the slit. Find the separation between 2nd bright fringe on both sides of
the central maximum.
8. What are Newton's rings and how are they formed Explain how Newton's rings setup can be
used for the determination of wavelength of monochromatic source of light?
In a grating, which spectral line in 4th order will overlap with 3rd order line of 5419 A0?
UNIT V
9. What is damped oscillation? Derive equation of motion for damped Oscillation. Discuss condition
for over damped motion.
A body of mass 5 gms is subjected to an elastic force of 40 dyne/cm, and a frictional force of
5 dyne-sec/cm. If it is displaced through 2 cm and then released. Find whether the resulting
motion is oscillatory or not? Also find the time period if it is oscillatory.
10. Distinguish between free and forced oscillations.
The wave function for a light wave is given by 103 sin x 106X 9 x1014 t Determine
the speed, wavelength and frequency of the wave?