JNTU Previous Question papers,B-Tech Supplementary Engineering physics Aug/Sep-2008

JNTU Previous Question papers,

B-Tech Supplementary Engineering physics

Set-III Aug/Sep-2008


1. (a) Differentiate between interference and diffraction.

(b) Explain Rayliegh’s criterion for resolving power of a telescope.

(c) A plane transmission grating having 6000 lines/cm is used to obtain a spectrum of light from a sodium lamp in the second order. Calculate the angular separation between two sodium lines D1 and D2 of wavelengths 5890 A.U. and 5896 A.U.


2. (a) What is meant by double refraction?

(b) Explain briefly optic axis and its characteristics.

(c) Discuss the construction of a nicol prism.


3. (a) What is meant by superconductivity? Explain.

(b) Show that the superconductors are perfect diamagnetic materials.

(c) Write some of the applications of superconductors.


4. (a) Explain the terms

i. absorption,

ii. spontaneous emission

iii. stimulated emission

iv. population inversion, relating to laser.

(b) Describe the principle of lasing action.

(c) Mention the important characteristics of laser beam.


5. (a) Derive expressions for the numerical aperture and the fractional index change

of an optical fibre.

(b) Explain the advantages of optical communication system.

(c) The numerical aperture of an optical fibre is 0.39. If the difference in the

refractive indices of the material of its core and the cladding is 0.05, calculate

the refractive index of material of the core.


6. (a) Explain the various properties of paramagnetic materials.

(b) Explain why the paramagnetic materials does not show Meissner effect.

(c) Mention the salient feature of the ferro-magnetic materials.


7. (a) Define Miller indices. Sketch the following atomic planes in a simple cubic

structure (010), (110) and (111).

(b) Derive an expression for the inter-planar distance in terms of Miller indices

for a cubic structure.


8. (a) Write in detail the different kinds of crystal imperfections.

(b) Explain the significance of Burgers vector.

Leave a Comment