Jawaharlal Nehru Technological University Kakinada 2012-1st Year B.Tech 1st st semester Engineering Physics R10 Set no:4 - Question Paper

Set Code No: R10103 / R10
No. 4
I B.Tech I Semester Regular/Supplementary exams January 2012
ENGINEERING PHYSICS - I (Common to all branches)
Time: three hours Max Marks: 75
ans any 5 ques. All ques. carry equal marks
1.(a) discuss why the centre of Newtons rings is dark in the reflected system.
(b) define how you would use Newtons rings to determine the wavelength of a
monochromatic radiation and derive the relevant formula.
(c) In Netons rings experiment, the diameter of the tenth ring modifications from 1.40 cm to 1.27 cm when a liquid is introduced ranging from the lens and the plate. compute the refractive index of the liquid.[3M + 8M + 4M]
2.(a) elaborate the kinds of diffraction and provide the differences ranging from them.
(b) find the condition for primary and secondary maxima in Fraunhofer diffraction due to
single slit and derive an expression for width of the central maxima.[6M + 9M]
3.(a) discuss Brewsters legal regulations.
(b) define the construction and action of nicol prism.
(c) obtain the polarizing angle for a glass of refractive index 1.732.[4M + 7M + 4M]
4.(a) describe crystal lattice, unit cell, lattice parameter and coordination number.
(b) define the FCC crystal structure and find the expression for its packing factor.
(c) Iron has BCC structure beneath 910 oC and is FCC structure above 910 oC. The atomic radius of an atom is the identical in both the cases. compute the ratio of the packing densities of bulk iron in the 2 structures at beneath 910 oC.[4M + 7M + 4M]
5.(a) Sketch the ( one two 2) and ( 0 2) planes in a cubic unit cell.
(b) State and derive Braggs legal regulations.
(c) How do distinguish ranging from the simple cubic, BCC and FCC using powder X-ray
diffraction data?[4M + 5M + 6M]
6.(a) define the
(i) spontaneous emission, (ii) stimulated emission, (iii) absorption and (iv) population inversion. (b) find the relation ranging from Einsteins coefficients.[8M + 7M]
7.(a) describe acceptance angle and numerical aperture. Derive the expressions for for both of
them.
(b) compute the number of modes propagating in an optical fiber of core of 6µm diameter,
(given that the indices are 1.45 and 1.44 for core and cladding respectively) while operated at a wavelength of 0.623 µm.[11M + 4M]
8.(a) discuss various kinds of scans in NDT.
(b) discuss different applications of ultrasonic testing.[8M + 7M]

Earning:   Approval pending.