ANNA UNIVERSITY QUESTIONS

PHYSICS – I (SEMESTER I -2008)
Unit I

Explain how ultrasonic waves can be produced by using piezoelectric crystal and write any four applications of ultrasonics.

Describe the production of ultrasonic waves by magnetostriction method and mention some of its applications.

i) Describe the different methods of detecting ultrasonicEx waves.
ii)With theory, explain the method of determination of velocity of ultrasonic waves with liquid using acoustic grating

i) In ultrasonic NDT what are the three different scan displays in common use?
ii)Explain the ultrasonic imaging for study of movement of heart(sonogram)

Unit II

For atomic transitions, derive Einstein coefficients and hence deduce the expressions for the ratio of spontaneous to stimulated emissions rate.

i) Describe the construction and working of He-Ne laser.
ii)Discuss the industrial applications of laser

i) Explain the construction and working of CO2 laser
ii) Describe the construction and reconstruction of Hologram

i) Explain the working of homojunction semiconductor laser
ii)Explain the working of Nd:YAG laser

Unit III

i) Explain the classification of optical fibre in detail
ii)Explain the double crucible method of fibre manufacturing

i) Explain the fibre optic losses and attenuation due to scattering, dispersion
bending in fibre optics
ii)Explain in detail fibre optic communication system.

i) Explain the working of both intensity modulated and phase modulated sensors
given examples for each.
ii)Explain the construction and working of fibre optic medical endoscopy.

i) Define numerical aperture
ii) Derive an expression for numerical aperture and angle of acceptance in
terms of refractive index of the core and fibre.
iii)Explain spicing of fibres.

Unit IV

i) Derive an expression for the de broglie wavelength .what are the characteristics
of matter waves.
ii)Derive Planck’s law of black body radiation and deduce energy expression for
longer wavelength and shorter wavelength.

i) Deduce the time independent Shroedinger wave equation.
ii)Explain the application of shroedinger equation to one dimensional potential
well.

i) What is the principle of electron microscopy
ii) With schematic diagram explain the construction and working of scanning
electron microscope.

4. What is Compton Shift? Derive the expression for Compton shift

Unit V

1. i) show that the atomic packing factor for HCP and FCC are same
ii) What are miller indices. Explain how they are determined?

2. i)Define the terms Atomic radius, and packing factor
ii) Explain the above for Sc, BCC, and FCC

3. i)Explain the following structures
a) NaCl b) diamond c) ZnS
ii)Explain the following crystal defects in detail
a) Point defects b) Line defects c) Surface defects.

4. i) what are lattice parameters of a unit cell
ii) Explain the different crystal systems and obtain Bravais lattices
iii)Define a) Space lattice b) Basis