Cochin University of Science and Techology (CUST) 2011-2nd Sem B.E Engineering Physics B.Tech 1- exam paper

Engineering Physics
(IT/CS/EC/CE/ME/SE/EB/EI/EE/FT)
2006 Scheme

Time:3-hours Maximum Marks:100

PART-A (8x5=40)
1)
a) elaborate anti-reflecting coatings?Give an application.
b) discuss Fresnel's and Fraunhoffes diffraction.
c) Distinguish ranging from plane polarized,circularly polarized and elliptically polarized light.
d) discuss the terms stimulated emission and population inversion.
e) What is meant by a mode.compare single mode and multimode fibres.
f) What is Heisenberg's uncertainity principle.Explain the non-existance of fine electrons in the nucleus.
g) State Moseley's legal regulations.Discuss 3 applications.
h) elaborate Miller Indices? Sketch (100),(110)and(111) plane of a cube crystal.

PART-B (4x15=60)
2)
a) What is an air-wedge? define the method of finding the diameter of a thin wire the air-
wedge arrangement. Derive the formula used. (8)
b) How to test the planeness of a glass plate using air wedge arrangement. (4)
c) Light of wavelength 6000 A falls normally on a thin wedge shaped film of refractive index 1.4 forming fringes that are two mm apart.Find the angle of the wedge. (3)
OR
3) a) define the construction and working og a nicol prism. (8)
b) State and discuss Biot's legal regulations of rotatory polarization. describe specific rotatory power of
an optically active substance. (4)
c) Plane polarized light passes through a glass plate with its optical axis parallel to
the faces.Calculate the thickness of the plate for which the the emergent beam will
be circularly polarized.(Given that R.Ie=1.5533 and R.Io=1.5442 and wavelength=5x10(to the power of -5). (3)


4)
a) discuss the structure and working of a ruby laser with a neat energy level diagram. (8)
b) Mention special features of laser beam compared to other beams of light produced by
conventional sources. (5)
c) Write any 2 applications of Ultrasonics. (2)
OR
5)
a) discuss the principle of propagation of light through optical fibres. (4)
b) describe the numerical aperture of an optical fibre and derive an expression for it. (8)
c) An optical fibre has a numerical aperture 0.32. The refractive index of cladding is
1.48. compute the refractive index of the core, accptance angle of the fibre and the
fractional refractive index change.
6)
a) elaborate matter waves ? Deduce an expression for the de-Brogli wavelength. (4)
b) Derive the time independent Schrodinger formula for a single practice. (8)
c) If the uncertainity in the position of an electron is 4x10(to the power of -10)m
,calculate the uncertainity in its momentum. (3)
OR
7)
a) State and discuss Raman Effect based on quantum theory. (6)
b) Write short note on
i) Pauli's exclusion principle
ii) zeeman effect
iii) Nuclear fusion (9)
8)
a) discuss d.c and a.c Josephon's effect of super conducters. (2)
b) explain BCS Theory of Super conductivity. (4)
c) Derive Bragg's legal regulations for X-ray diffractions. define how Bragg's spectrometer is used
to determine the wavelength of X-ray beam. (9)

X.............X

Earning:   Approval pending.