Registration No: B.Tech. Total Number of Pages: 03 15BS1102 t" Semester Back Examination: 2017-18 Physics-I BRANCH (s): , AEIE, BIOTECH, CHEM, CIVIL, CSE, ECE, EEE, EIE, ELECTRICAL, MANUTECH, MECH, MINERAL, MINING, MME, PE, TEXTILE Time: 3 Hours ETC, lEE, IT, Max Marks: 100 Q.CODE: B843 Answer Part-A which is compulsory and any four from Part-B. The figures in the right hand margin indicate marks. Part-A (Answer all questions) (2 x 10) Select the correct answer of the followings: Q1 a) b) In simple harmonic motion kinetic energy is maximum at (i)equilibrium position (ii) extreme position (iii) any position between extreme and minimum position (iv) none of the above The maximum velocity of a particle executing SHM represented by x=Asinwt c) at time t occurs at (i) x=O: (ii) x=A; (iii) x=-A; (iv) x=A/2 What should be the path difference between two coherent waves of wavelength such that there will be constructive interference? (i)NA. (ii) (2N+1)A. (iii) (2N-1)A. (iv) none of the above d) e) What is the phase difference between two waves originating from two consecutive Fresnel's half period zones? (i)O (ii) n/2 (iii) n (iv) Zrt What type of wavefront is incident in the case of Fresnel's diffraction? f) The refractive (i)Plane (ii) Spherical (iii) cylindrical (iv) elliptical index of certain glass is 1.5. What is the polarizing angle for this glass surface? (i)55° (ii) 56° (iii) 57° (iv) 58° g) The divergence of a position vector in XYZ plane is h) (i)3 (ii) 9 (iii) 12 (iv) 15 Velocity of light in free space is given by c i) (i)c=v~oEo (ii) C=V~oNEo (iii) c=VEoN~o (iv) c=lN~oEo Through what potential difference should an electron be accelerated j) its de-broglie wavelength becomes 5500 Ao. (i)4.98x10-6 V (ii) 4.98x10-s V (iii) 4.98x10-4 V (iv) 4.98x10-3 V Name a phenomenon into matter. (i)Compton effect where energy is converted (ii) photoelectric effect so that (iii) pair production (iv) Radioactive decay Q2 a) b) Answer the following questions: What do you mean by critically damped harmonic oscillation? (2 x 10) Write its applications. Show graphically under damped, over damped and critically damped harmonic oscillations.
c) What are the conditions d) e) Write few differences between interference Define optical rotation and write its unit. f) g) State Gauss law in electrostatic State Stoke's theorem. h) Show that vector A=(x+3y)i + (y+ az)j i) What is the need of Quantum mechanics? j) What is quantum for sustained interference? and diffraction. field. Write its integral and differential form. +Ix+azlk is solenoidal. mechanical tunneling? Part-B (Answer any four questions) Q3 a) A damped oscillator is subjected to a damping force proportional to its velocity. Set up the differential equation of the oscillator. Discuss under damped oscillation. Explain logarithmic decrement. (5) b) The time period of simple harmonic oscillator is 4s. It is subjected to a damping force proportional to its speed with damping co-efficient O.l/s. Find (5) the time period and logarithmic decrement when subjected to damping forces. Q4 e) Differentiate between progressive and stationary a) Give the theory of Newton's rings and how to determine of transparent b) (5) the refractive index (5) rings. It is found that the ntl"ldark ring due tOAl coincides with (n+l)th dark ring for A2. If the radius of curvature em, find the diameter A slit illuminated from (5) liquid using it. A source of light emitting two wavelengths Al=6000 AO and A2=4500 AO is used for Newton's c) wave. a biprism of the convex surface is 100 of nth dark ring for A2. by a monochromatic of refractive light is placed at a distance of 10 cm (5) index 1.5 and base angle 2°. If the distance between two dark fringes is 0.18 mm, as observed on a screen placed at a distance of 1 m from the biprism. Find the wavelength of light. Q5 a) Write some similarities and dissimilarities between zone plate and convex (5) lens. b) A plane diffraction light of wavelength grating of width 2.5 cm has 1500 rulings. Monochromatic 5893 AO is incident normally on it. Find-the angle at which (5) second order principal maximum occurs. e) In Fraunhofer diffraction due to single slit, obtain the conditions for principal (5) maxima, secondary maxima and minima. Show the intensity distribution curve graphically Q6 a) in this diffraction Explain the construction pattern. and working of Nichol prism with suitable diagram. (5) b) Distinguish between e-ray and o-ray. (5) e) The refractive indices of a double refracting material for o-ray and e-rays for wavelength, 5500 AO are 1.588 and 1.594 respectively. Calculate the required (5) thickness of the material for, (i) half wave plate (ii) quarter wave plate. .,
Q7 a) (5) With the help of Gauss divergence theorem, show that the volume of a sphere is rrd3/6, where d is the diameter of the sphere. Q8 b) Derive electromagnetic wave equations in conducting c) dissipative terms. Distinguish conduction current and displacement medium and write the (5) (5) current. a) Define Poynting vector. Deduce Poynting theorem for the flow of energy in an (5) b) electromagnetic field. State Heisenberg's uncertainty electrons (5) and phase (5) by eigen (5) principle and using it show that cannot reside inside a nucleus. Q9 c) Define group velocity velocity. a) The probability functions that 411, 412, 413 and find a relation between group velocity a system can be in the states are X, 1/3, X respectively. represented Write the wave function for (5) b) the system. If the energy eigen values for the given states are 2 eV, 3 eV and 4 eV respectively, find the energy expectation value. Write the Schrodinger's equation for an infinitely deep one dimensional (5) c) potential well and find expression for the wave function and energy of the particle. Calculate the expectation value of x-component of momentum of a free particle in a box of length I, lV=v(2/1) [Sin (nrrx/I)) .,