Engineering Physics 1 - Dec 2013

First Year Engineering (Semester 1)

TOTAL MARKS:
TOTAL TIME: HOURS

1 What is cavitation?(2 marks) 10 what is Schottky defects?(2 marks) 11.(a)(i) What is inverse piezo-electric effect? Describe the method of producing ultrasonic waves by piezo-electric method. (10 marks) 11.(a)(ii) Describe about any two methods using which ultrasonic waves can be detected?(6 marks) 11.(b)(i) Give an account on the application of ultrasonic in? Drilling
b) Welding
Cleaning (3 marks) 11.(b)(ii) Explain the process of non destructive testing of materials using ultrasonic waves?(6 marks) 12.(a)(i) describe the construction of Nd-YAG laser and using an energy level diagram explain the working of Nd-YAG laser.(10 marks) 12.(a)(ii) Discuss about the different pumping schemes used to achieve population inversion in lasers? (6 marks) 12.(b)(i) Describe the method of construction and reconstruction of images using holography?(10 marks) 12.(b)(ii) Outline the use of lasers in welding and cutting of materials?(6 marks) 13.(a)(i) Explain the principle and propagation of light through an optical fiber and obtain the expression for numerical aperture and acceptance angle?(10 marks) 13.(a)(ii) Explain the working of fibre endoscope?(6 marks) 13.(b)(i) With the help of block diagram explain the working of an optical communication system. What are its advantages over conventional wire systems?(10 marks) 13.(b)(ii) Give an account on dispersion and bending losses in optical fibres?(6 marks) 14.(a)(i) What is Compton Effect? Obtain an expression for Compton shift. (10 marks) 14.(a)(ii) Describe briefly about the working of scanning electron microscope?(6 marks) 14.(b)(i) Write Schrodinger's equation for a particle in a box. Solve it to obtain eigen values and eigen functions and show that they are discrete?(10 marks) 14.(b)(ii) Obtain Rayleigh Jeans law from Planck a theory. Is Rayleigh Jeans law valid for all wavelengths?(6 marks) 15.(a)(i) Explain the hexagonal closed packed structure and obtain its atomic packing factor? (10 marks) 15.(a)(ii) Sodium chloride crystallizes in FCC structure. The density of sodium chloride is 2.18x103 Kg/m³. Calculate the distance between two adjacent atoms. The atomic weight of sodium and chlorine are 23 and 35.5 respectively?(6 marks) 15.(b)(i) What is line defect? Explain edge dislocation using a neat diagram. What are positive and negative edge dislocations?(10 marks) 15.(b)(ii) Describe the method of determining Miler indices of a given plane in a cubic lattice? (6 marks) 2 A nickel rod is used to produce ultrasonic waves of frequency f. if ultrasonic waves with frequency 2f are to be produced what should be the length of the nickel rod?(2 marks) 3 What is the function of helium atom in He-Ne laser?(2 marks) 4 Give any two differences between homo-junction and hetero-junction lasers?(2 marks) 5 For a step index optical fiber with a core of refractive index 1.48 and numerical aperture 0.649, calculate the refractive index of cladding?(2 marks) 6 What is the principle by which temperature is measured using a fiber optical sensor?(2 marks) 7 State Wien's displacement law?(2 marks) 8 An electron is constrained to a one dimensional potential box of 0.1 nm width. Obtain the first eigen value of the electron in electron volts (h=6.62x10^-34) Js)(2 marks) 9 Give the cooordination number of BCC and FCC structures?(2 marks)