Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU)) B-Tech 1st Semester (First Semester) 2015-2016 NAS 101 Engineering Physics 1 Question Paper
(Following Paper ID and Roll No. to be ?lled in your
Answer Book)
Paper ID: 181504 ' RonNo,
B.Tech.
(SEM. I) THEORY EXAM. 2015-16
ENGINEERING PHYSICS-I
[Time : 3 hours] J [Total Marks : 100]
SECTION -A
l. Attempt all parts. all parts carry equal marks. Write
answer of each part in short. (2x10=20)
(a) How the negative results of Michelson-Morley
experiment interpreted ?
(b) Find relativistic relation between energy and
momentum.
(c) If uncertainty in the position of a particle is equal
to de Broglie wavelength, what will be uncertainty
in the measurment of velocity ?
((1) Write the characteristics of wave function,
(e) Why the center of Newton?s ring is dark ?
(f) De?ne plane fo polarization and plane fo vibaration.
82000 (1) [13.10.]
Note : Attempt any five questions.
2.
(g) De?ne optic axis of doubly refracting crystal.
(h) What is Rayleigh?s criterion of resolution?
(i) De?ne metastable state.
(i) Give few importat applications of optical ?bre.
SECTION-B
(5 X 10:50)
What do you mean by proper length? Derive the
expression for relativistic length. Calculate the
percentage contraction of a rod moving with a velocity
of 0.6c in a direction inclined at 30? to its own length.
Show that the relativistic invariance of the law of
conservation of momentum leads to the concept of
variation of mass with velocity.
State Heisenberg?s uncertainty principle. Prove that
electron cannot exist inside the nucleus and proton can
exists.
Explain the physical signi?cance of wave function.
Derive Schrodinger?s time independent wave equation.
Explain the formation of Newton ?5? if in a newton?s rings
experiment, the air in the interspace is replaced by a
liquid of refractive index 1.33 in what proportion would
the diameter of the rings changed?
82000 (2) NAS-l 01
Discuss the phenomenon of diffraction at a single slit
and show that intensities of successive maxima are
.._4_ 4 . 4
'97r2.2572'2.49772
Discuss the construction and working of a He-Ne laser.
Compare it with Ruby Laser.
Describe the basic principle of communication of wave
in optical ?bre. A step index ?bre has core refractive
index 1.468, cladding refractive index 10462. Compute
the maximum radius allowed for a ?bre, if it supported
only one mode at a wavelength 1300 nm.
SECTION-C
Note: Attempt any two questions from this section.(2>< 15=30)
10.
11.
(a) Derive the Galilean transformation equations and
show that its acceleration components is invariant.
(b) If the kinetic energy of a body is twice its rest mass
energy, ?nd its velocity.
(0) Explain de?Broglie?s hypothesis. Discuss the
outcome of Davisson-Germer?s experiment in
detail.
(a) Explain the phenomenon of interference in thin
?lm due to re?ected rays.
C
82000 (3) [P.T.O.]
(b)
(C)
12. (a)
(b)
(C)
82000
A diffraction grating used at normal incidence gives
a yellow line (,1 =6000A) in a certain spectral
order superimposed on a blue line ( ,1 =4800A) of
next higher ?order. If the angle of diffraction is
sin?l (3/4), calculate the grating element.
Describe the construction and working of Nicol
prism.
Prove that vvag=c2 , Where Vp =phase velocity and
vg=group velocity.
Discuss the ?fferent types of optical ?bre in detail.
In a Ruby laser, total number of Cr+3 is 2.8)(10l9 . If
the laser emits radiation of wavelength 7000A
calculate the energy of the laser pulse.
Physical Constants :
Mass of electron m0 = 9.] x10?31 kg
Mass of proton mp = 1.67x10?27 kg
Speedoflight c=3x108 m/s
Planck?s Constant h = 6.63x10?3? J/s
Charge on electron e = 1.67x10?2" kg
Boltzmann?s Constant k $1.38x10?23 m2 kg 5?lel
-?_- x _-__
(4) NAS-lOl
This post was last modified on 29 January 2020