Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU)) B-Tech 1st Semester (First Semester) 2017-2018 RAS101 Engineering Physics Question Paper
(Following Paper ID and Roll No. to be filled in your Answer Book)
PAPER ID: 9001 Roll No.
B. Tech.
(Semester?I) Theory Examination 2017 - 18
ENGINEERING PHYSICS-I
Time: 3 Hours Total Marks: 70
Note: Attempt all Sections. If require any missing data; then choose suitably.
SECTION A
1. Attempt all questions in brief. 2 x 7 = 14
a. Is earth an inertial or non-inertial frame of reference? J ustify your answer.
b. What is Wien?s displacement law?
0. What do you mean by group velocity?
d. Define dispersive power of a plane transmission diffraction grating.
e. Differentiate between spontaneous and stimulated emission of radiation.
f. What do you mean by specific rotation?
g. What do you mean by acceptance angle?
SECTION B
2. Attempt any three parts of the following: 7 x 3 = 21
a. Obtain Galilean transformation equations. Show that length and acceleration are
invariant under Galilean transformations.
b. Derive Planck?s radiation law. Show that Planck? s formula for the energy
distribution in a thermal spectrum is applicable for all wavelengths.
0. Give the construction and theory of plane transmission grating. Explain the
formation of spectra by it.
d. What is the advantage of four level laser systems over three level laser systems?
Describe the construction and working of ruby laser.
e, What is holography? Explain the basic principle of holography using construction and
reconstruction of image.
SECTION C
Attempt any one part of the following: 7 x 1 = 7
(a)
Deduce the relativistic velocity addition theorem. Show that it is consistent with
Einstein?s second postulate.
(b) What do you mean by time dilation? Establish a relation for it. At what speed
should a clock be moved so that it may appear to lose 1 min each hour?
Attempt any one part of the following: 7 x 1 = 7
(a) What is the concept of de-Broglie matter waves? Describe Davisson?Germer
experiment and prove that electrons possess wave nature.
(b) Find an expression for the energy states of a paiticle in a one ?dimensiona1box.
Determine the probability of finding a paiticle trapped in a box of length L in the
region from 0.45L to 0.55L for the ground state.
Attempt any one part of the following: 7 x 1 = 7
(a) Discuss the formation of interference fringes due to a wedge-shaped thin ?lm seen
by normally re?ected monochromatic light and obtain an expression for the fringe
width.
(b) Obtain an expression for the intensity distribution due to Fraunhofer diffraction at a single
slit. A light of wavelength 6000A falls normally on a slit of width 0.10 mm. Calculate the
total angular width of the central maximum.
Attempt any one part of the following: 7 x 1 = 7
(a) Explain the phenomenon of double refraction and discuss the various characteristics
of ordinary and extraordinary rays. Find the thickness of a quarter wave plate of
quaitz for light of wavelength 5893 A. The refractive indices for ordinary and
extraordinary rays are 1.544 and 1.553 respectively.
(b) What do you mean by optical activity? Give Fresnel?s theory of optical activity and
derive the necessary expression for the optical rotation.
Attempt any one part of the following: 7 x 1 = 7
(a) Explain single mode and multimode fibers. Differentiate between characteristic
properties of single mode and multimode fibers.
(b) Explain dispersion and attenuation in optical fiber. The optical power, after
propagating through a 500 m long fiber, is reduced to 25% of its original value.
Calculate ?ber loss in dB/km.
This post was last modified on 29 January 2020