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Gujarat Technological University Aeronautical EngineeringSemesterI Physics previous As you want to get the Gujarat Technological University Aeronautical EngineeringSemesterI Physics previous years question papers so here is the information of the same for you: Gujarat Technological University Aeronautical EngineeringSemesterI Physics previous years question papers Instructions: 1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks. Q.1 Answer the following in short 14 (a) State the characteristics of Laser. (b) Define reverberation time (c) Define piezoelectric effect (d) What do you mean by primitive cell (e) Give the full form of NDT (f) Give two examples of trivalent impurities for semiconductors (g) Explain the term lattice and basis (h) State the types of the optical fibers. (i) What is the transition temperature for mercury. (j) Define superconductivity. (k) Define shape memory effect (l) Give two examples solid lasers (m) State the main components of the optical fiber (n) Define sound intensity. Q.2 (a) Answer the following in detail 1 Explain the construction and working of Nd:YAG laser 05 2 Compare typeI and typeII superconductors. 02 (b) Answer the following in detail 1 Discuss the advantages of optical fiber communication system over the conventional system. 05 2 Calculate the NA , the acceptance angle of the fiber having n1 = 1.52 and n2 = 1.45. 02 OR (b) Answer the following in detail 1 Discuss the properties , types and applications of metallic glasses 05 2 A hall has volume of 7500 m3 . What should be the total absorption in the hall if the reverberation time of 1.5 sec is to be maintained ? 02 Q.3 Answer the following in detail (a) Derive the relation between Einstein’s coefficients A and B . 05 (b) State the characteristics of laser light .Explain the terms stimulated emission, spontaneous emission, population inversion, optical resonators and active medium 05 (c) An ultrasonic source of 0.09 MHz sends down a pulse towards the seabed which returns after 0.55 sec. The velocity of sound in water is 1800 m/s .Calculate the depth of the sea and wavelength of the pulse . 04 2 OR Q.3 Answer the following in detail (a) Explain the terms magnetostriction and piezoelectric effect. Discuss any one method of production of ultrasonic waves 05 (b) What is meant by time of reverberation? Discuss Sabine’s Formula. 05 (c) Calculate the capacitance required to produce ultrasonic waves of 106 Hz with an inductance of 1 henry. 04 Q.4 Answer the following in detail (a) What do you mean by Miller indices ? Explain with proper example how to determine Miller indices. 05 (b) Define atomic radius and packing fraction for the crystal system. Calculate atomic radius and packing fraction for simple cubic structure and face centered cubic structure. 05 (c) Sodium metal with bcc structure has two toms/ unit cell. The radius of sodium atom is 1.85 A. Calculate the electrical resistivity at 0 o C if the classical value of mean free time at this temperature is 3X10 14 sec 04 OR Q. 4 Answer the following in detail (a) Deduce expression for electrical conductivity of conducting material and hence obtain Wiedemann Franz law. 05 (b) Discuss the properties of superconductors. 05 (c) Calculate the inter planner spacing for a ( 3,1,2 ) plane in a simple cubic lattice whose lattice constant is 1.909 X1010 m. 04 Q.5 Answer the following in detail (a) What is a varactor diode. Explain its working and applications 05 (b) Discuss the liquid penetrant method of NDT in detail 05 (c) A silicon plate of thickness 1mm, breadth 1 cm and length 10 cm is placed in a magnetic induction 0.5 weber/m2 acting perpendicular to its thickness. If 1 A current flows along its length, calculate the Hall voltage developed if the Hall coefficient is 3.66 x 104 m3/C. 04 OR Q.5 Answer the following in detail (a) Explain the term Hall effect. Derive the relation between Hall voltage and Hall coefficient 05 (b) Short notes : (1) shape memory effect (2) LED 05 (c) Find the relaxation time of conduction electron in a metal having resistivity 1.54 x 108 ohmm and electron density 5.8 x 1028 electrons/m3. Instructions: 1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks. Q.1 14 1 Define absorption coefficient. 2 Expand the term: ‘SONAR’. 3 What are crystalline materials? Give its example. 4 State the applications of Hall effect. 5 Expand the term: ‘LASER’. 6 State the working principle of fiber optics. 7 Give the statement of WeiedmannFranz law. 8 Define critical temperature. 9 What are metallic glasses? 10 List the methods for production of nanomaterials. 11 Name different types of biomaterials. 12 State the working principles of holography. 13 Mention the objectives of NonDestructive Testing (NDT). 14 What is the frequency range of the audible sound? Q.2 (a) Discuss various factors affecting the acoustics of buildings and give their remedies. 07 (b) What are ultrasonic waves? Explain with required circuit diagram the generation of ultrasonic waves with piezoelectric effect. 07 OR (b) Discuss the applications of ultrasonic waves 07 Q.3 (a) Explain the construction, operation, merits and demerits of solar cell. 07 (b) Derive the mathematical relation between inter planer distance and cube edge with required diagrams. 04 (c) Calculate the inter planer spacing for a (3 1 1) plane in a simple cubic lattice whose lattice constant is 2.109 A0. 03 OR Q.3 (a) Give the construction,applications and merits & demerits of the Light Emiting Diode. 07 (b) Mention the Properties of LASER. 04 (c) Prove that the ratio of spontaneous emission and stimulated emission is proportional to the cube of frequency. 03 Q.4 (a) Discuss in detail the advantages of fiber optics cable over metallic cable. 07 (b) Compare type 1 and type 2 superconductors. 04 (c) For InP laser diode, the wavelength of light emission is 1.55micrometer. What is its band gap in eV? 03 OR 2 Q. 4 (a) What are super conductors? Explain few important properties of superconductors. 07 (b) What is magnetic levitation? Explain in details with its applications. 04 (c) Find the thermal conductivity of copper at 200C with free electron density of 8.48 x 10 28 m3 . The thermal velocity of Cu at 200 C is 1.1536 x 10 5 m/s with a mean free path of 2.8138 nm. 03 Q.5 (a) Write the properties and applications of nanomaterials. 07 (b) Give the difference between metallic and nonmetallic glasses. 04 (c) The critical temperature of Nb is 9.15 K. At zero kelvin the critical field is 0.196 tesla. Calculate the critical field at 6K. 03 OR Q.5 (a) Describe Shape Memory Alloy in detail. 07 (b) Compare destructive testing with Nondestructive testing. 04 (c) Calculate the frequency to which a piezo electric oscillator circuit should be tuned so that a piezo electric crystal of thickness 0.1 cm vibrates in fundamental mode to generate ultrasonic waves. (Young’s Modulus and density of material of crystal are 80 Gpa and 2654 kg / m3) Instructions: 1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks. Q.1 Answer the following in short. 14 i Define unit cell ii State the properties of LASER iii What is the life time of charge carrier in metastable state? iv What is standard intensity? Give its value. v Define reverberation time vi Define piezoelectric effect vii Define total internal reflection viii State the main components of optical fiber communication system. ix Define the transition temperature for superconductivity x Define NDT xi What do you mean by metallic glasses? xii Give two examples of pentavalent impurities. xiii Define lattice and basis. xiv State the full form of LASER Q.2 (a) Answer the following in detail. i. Discuss the advantage of optical fiber communication system over the conventional coaxial communication system 4 ii. Compare typeI and typeII superconductors 3 Q.2 (b) Answer the following in detail. i. Derive the expression for acceptance angle & Numerical aperture of an optical fiber. 4 ii. Calculate the NA, the acceptance angle of the fiber having n1 = 1.48 and n2 = 1.43. 3 OR Q.2 (b) Answer the following in detail. i. Discuss the properties , types and applications of metallic glasses 4 ii. The volume of the room is 600m3 . the wall area of the room is 220 m2 the floor area is 120 m2 and ceiling area is 120 m2 . The average sound absorption coefficient for wall is 0.03 , for ceiling is 0.8 and for floor it is 0.06 . calculate reverberation time. 3 Q.3 Answer the following in detail. i. Describe the construction and working of Nd YAG laser. 5 ii. Derive the relation between Einstein ‘s ‘A’ and ‘B’ coefficients. 5 iii. Calculate the frequency to which piezoelectric oscillator circuit should be tuned so that a piezoelectric crystal of thickness 0.1cm vibrates in its fundamental mode to generate ultrasonic waves. (Young’s modulus and the density of material of crystal are 80 giga Pascal and 2654 kgm3). 4 OR Q.3 Answer the following in detail. i. Explain the terms magnetostriction and piezoelectric effect. Discuss any one method of production of ultrasonic waves 5 ii. What is meant by time of reverberation? Discuss Sabine’s Formula. 5 iii. The Hall coefficient (RH) of a semiconductor is 3.22 x 104 m3 C1 . Its resistivity is 9 x 103 ohmm. Calculate the mobility and carrier concentration of the carriers 4 Q.4 Answer the following in detail. i. Discuss in detail the ultrasonic flaw detection. 5 ii. What are Miller indices ? Explain with proper example how to determine miller indices. 5 iii. Calculate the inter planner spacing for a ( 3,1,1 ) plane in a simple cubic lattice whose lattice constant is 2.109 X1010 m. 4 OR Q.4 Answer the following in detail. i. Explain how the materials are classified into conductors, semiconductors and insulators with the help of energy band diagrams. 5 ii. State any five factors affecting the acoustics of the building and give at least two remedies for each. 5 iii. What is the resultant sound level when a 70 dB sound is added to a 80 dB sound? 4 Q.5 Answer the following in detail. i. Explain the term Hall effect. Derive the relation between Hall voltage and Hall coefficient 5 ii. Discuss the important postulates of free electron theory of metals 5 iii. Short notes : (1.) LED ( 2 ) solar cell 4 OR Q.5 Answer the following in detail. i. Discuss the liquid penetrate method of NDT in detail 5 ii. Discuss the properties of superconductors. 5 iii. Short notes : (1 ) crystal system ( 2) Shape memory effect 4 Contact Details: Gujarat Technological University Sabarmati, Koba Highway, Near VISAT Three Road, Nr. Vishwakarma Government Engineering College, Chandkheda, Ahmedabad, Gujarat 382424 079 2630 0499 India Map Location: Last edited by Neelurk; May 28th, 2020 at 11:12 AM. 
