Physics - Jun 2014
First Year Engineering (Semester 1)
TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1(a)(1) Choose the correct option from the followings:
1. The rate of change of momentum is _______
(a) Acceleration(b) Force (c) Velocity (d) Momentum(1 marks) 1(a)(2) The motion of a vehicle on a horizontal road is due to______
(a)Engine of vehicle (b) driver of vehicle (c) Earth (d) friction between road and vehicle(1 marks) 1(a)(3) 1 V/m = _______
(a) 1 N/C (b) 1N (c) 1N/m (d) 1J/C(1 marks) 1(a)(4) The SI unit of resistivity is_______
(a)Ω.m2(b) Ω2.m(c) Ω.m (d) Ω.m3(1 marks) 1(a)(5) According to Faraday's law of electromagnetic induction, the rate of change of______ produced induced emf in a closed circuit
(a) Magnetic flux (b)Electric field(c)Magnetic field(d)None of above(1 marks) 1(a)(6) n a bar magnet, the magnetic field lines______
(a) are not present (b) depend upon cross section area of the magnet (c) go from N-pole to S-pole (d) go from S -pole to N-pole(1 marks) 1(a)(7) The interactive force between two charged particles is given by______ law.
(a) Newton's (b) Coulomb's c) Biot-savart (d) Faraday's (1 marks) 1(b)(1) Choose the correct option from the followings:
The unit of capacitance of capacitor is_______
(a) Henry (b) Ohm (c) Farad (d) Coulom(1 marks) 1(b)(2) AC ammeter measures ______ value of current
(a) Average (b) rms (c) entire (d) none of the above(1 marks) 1(b)(3) An inductor stores energy in its______
(a)Electric field (b) Conducting wire (c) Magnetic field (d) magnetic field and Electric field (1 marks) 1(b)(4) The equivalent resistance of two resistor conne cted in parallel with same value R is _______
(a) R/2 (b) 2R (c) 4R (d) R/4(1 marks) 1(b)(5) The upward force exerted by any fluid on object, placed in it, is called______
(a) Attractive force (b) Repulsive force (c) Adhesive force (d) Buoyant force(1 marks) 1(b)(6) The principle of a hydraulic lift used to raise heavy loads is the application of ________ law.
(a) Newton (b) Archimedes (c)Poiseiulle(d)Pasca(1 marks) 1(b)(7) If the force of 2N is applied on surface area of 2m 2 , the pressure acting on it is____
(a) 1 N/m2(b) 10 N/m2(c) 2 N/m2(d) 0.5 N/m (1 marks) 2(a)(1) Deduce Clausius -Mossotti equation. What is its significance?(4 marks) 2(a)(2) Calculate the polarizability and relative permittivity in hydrogen gas with a density of 9.8 × 1026 atoms/m3.Given the radius of hydrogen atom to be 0.5 Å(3 marks) 2(b)(1) Distinguish between hard and soft magnetic materials.(4 marks) 2(b)(2) A Magnetic field strength of 2×105A/m in applied to paramagnetic material with relative permeability of 1.01. Calculate the values of B and M.(3 marks) 3(a)(1) Discuss briefly about types of sound absorbing materials(4 marks) 3(a)(2) A hall has a volume of 12,500 m3and reverberation time of 1.5 sec. If 200c ushioned Chairs are additionally placed in the hall, What will be the new Reverberation time of the hall? The absorption of each chair is 1 O.W.U(3 marks) 3(b)(1) Explain with neat circuit the generation of ultrasonic waves using piezo-electric Oscillator. (4 marks) 3(b)(2) Describe any six applications of ultrasonic waves(3 marks) 4(a)(1) Write a short note on followings:
i) Isotopic effectii) Meissner effect(4 marks) 4(a)(2) Calculate the critical current for a superconducting wire of lead having diameter 1mm at 4.2 K. Critical temperature for lead is 7.18 K and H0 = 6.5 ×104A/m.(3 marks) 4(b)(1) Discuss the propert ies of LASER in detail.(4 marks) 4(b)(2) Define: i) Metastable state ii) Population Inversion iii) Pumping(3 marks) 5(a)(1) Discuss in detail the advantages of optical fiber over conventional metallic cable(4 marks) 5(a)(2) A silica optical fiber has a core of relative index 1.55 and a cladding of refractive index 1.47. Determine the critical angle, numerical perture and the acceptance angle for fiber(3 marks) 5(b)(1) Discuss in detail how the different properties of nonmaterial changes with reduction in size. (4 marks) 5(b)(2) Describe Electric arc method of CNT synthesis.(3 marks) 6(a)(1) Explain the two function properties of shape memory alloys in detail(4 marks) 6(a)(2) Write a short note on ultra capacitor (3 marks) 6(b)(1) Define :
i) Electric field Intensity ii) Electric Polarization iii) Magnetic susceptibility iv) Magnetization(4 marks) 6(b)(2) List out the difference between single mode fiber and multi mode fiber(3 marks) 7(a)(1) Discuss in detail, the procedure of data recording and reading in floppy disc.(4 marks) 7(a)(2) Discuss in detail quantum confinement.(3 marks) 7(b)(1) Compare between spontaneous and stimulated emission(4 marks) 7(b)(2) Explain the melt spinning technique to prepare etallic glasses(3 marks)