Applied Physics Exam Questions Bank Sem-1 PDF

Important question for University Examination. Applied Physics Module Topics Questions 1. Lasers Spontaneous and 1. Differentiate between spontaneous and stimulated stimulat...

Important question for University Examination. Applied Physics Module Topics Questions 1. Lasers Spontaneous and 1. Differentiate between spontaneous and stimulated stimulated emission, emission. (3) 2. Define stimulated emission and stimulated emission. (3) 3. Apply the concept of stimulated emission to explain the amplification of light in a laser. (3) population inversion, 1. What is population inversion, and why is it pumping, active medium important in laser operation? (3) & active center, 2. What is active medium and active centers. (3) Resonant cavity, 1. Describe the function of a resonant cavity in a laser. coherence length and (3) coherence time, 2. Define coherence length and its significance in laser Physics. (3) 3. What is coherence time, and how is it related to coherence length? 4. Define coherence length and coherence time Characteristics of lasers, 1) Discuss the characteristics of lasers. (3) He-Ne laser: construction 2) Draw the energy level diagram of a helium-neon and working. (He-Ne) laser (3) 3) Describe the construction and working principle of a He-Ne laser. (5) Application : (i)Basics of 1. Discuss the application of lasers (3) LiDAR(ii) Barcode reader 2. How does LiDAR use lasers to measure distances? (iii) Application of laser (3) in metal work 3. Discuss the application of lasers in metal work. (3) 2. Fibre Optics Critical angle, acceptance 1. Define Critical angle, acceptance angle, acceptance angle, acceptance cone, cone. (3) numerical aperture, total 2. Define numerical aperture, total internal reflection. internal reflection 3. Derive Numerical Aperture formula for a step index fibre. Discuss formation of acceptance cone with its importance. (5) Types of optical fibers: 1. Differentiate between single-mode and multimode Single mode & optical fibers. (5) multimode, step index & 2. Explain the differences between step-index and graded index graded-index optical fibers. (5)  3. How will you choose a fibre for long distance communication? Categorize the fibres for single mode and multimode fibres.(5) Attenuation, attenuation 1. Define attenuation in optical fibers. (3) coefficient, factors 2. What are the main causes of attenuation in optical affecting attenuation of fibers? (3) light on fibre optics 3. Fibre Optic 1. List the main advantages of using optical fiber Communication System, communication systems over traditional copper- Advantages of optical based systems. (5) fiber communication, 2. numerical 3. Interference in Interference in thin film 1. Why we see beautiful colours in thin film when it is Thin Film of uniform thickness, exposed to sunlight? (3) conditions of maxima and 2. What will happen to white light interference fringes minima for reflected if ordinary light is replaced by monochromatic system, light? (3) 3. Derive the condition for maxima and minima due to interference of light reflected from thin film of uniform thickness. (5) 4. Conditions for maxima and minima for wedge 1. Write the condition for maxima and minima due to shaped film interference of light reflected from thin film of wedge shaped film. (3) Newton’s rings for determination of 1. Show that the diameter of Newton’s nth dark ring is unknown monochromatic proportional to square roof of ring number. (5) wavelength and refractive 2. With the help of proper diagram and necessary Index of transparent expression explain how newton’s ring experiment is liquid useful to determine the radius of curvature of a plano-convex lens. (5) 3. How are newton’s rings experiments used to determine refractive index of liquid medium? (3) 4. AntiReflecting Coating 1. Discuss the condition required for a film to act as anti -reflection coating. 4.Electrodynamics Vector Calculus: 1) Numericals on grad, divergence & curl. (3) Gradient, Divergence, 2) What are the Scalars and Vector fields? How is a  Curl. del operator expressed? Explain the term ‘curl of a vector and state its significance’. Show that the divergence of the curl of a vector is zero. (5) 3) Explain the Physical significance of Divergence and Curl of a vector field with suitable example? (5) 4) Describe the physical significance of gradient, Divergence and Curl. 5) Explain the term ‘curl of a vector and state its significance’. Show that the divergence of the curl of a vector is zero. (5) Divergence theorem, 1) State Divergence and Stokes Theorem with their Stokes theorem significance. (3) Gauss’s law, Amperes’ 1) State Maxwell’s all four equations and give the circuital Law, Faraday’s significance of each. (5) law, Maxwell’s equations in 1) Derive Maxwell’s First equation and state its point form, significance. (5) Integral form and their 2) How will you state Faraday’s law in differential (in significance(Cartesian point) form explain with appropriate derivation. (5) coordinate only) 3) Obtain Ampere’s circuital law for static magnetic field in differential and integral form. (5) 4) State and derive Maxwells equation which describes how the electric field circulates around the time varying magnetic field (Differential form) (5) 5) Explain Gauss’s laws for static electric and static magnetic fields in differential and integral forms. (5) 6) State Maxwell’s equations in integral forms. (5) 5. Quantum Physics de Broglie hypothesis of 1) Define the terms Wave Packet, Phase velocity and matter waves, de Broglie group velocity. (3) wavelength for electron, 2) State de Broglie hypothesis and derive the Properties of matter expression of wavelength. Mention three properties waves, of matter waves. (5) 3) What are the properties of matter waves? (3) 4) ‘The phase velocity of matter wave is greater than the velocity of light’. Prove this statement. (5) Heisenberg’s Uncertainty 1) Discuss Heisenberg’s Uncertainty principle and principle prove that electrons cannot reside inside the nucleus Wave function and of an atom using the same principle. (5) probability density, 2) What is a wave function? State its Physical mathematical conditions significance. (3) for wave function, 3) What is HUP? Solve a numerical on it. (5) problems on de Broglie  wavelength, Need and significance of 1) Write the expression for Schrodinger’s time Schrödinger’s equations, dependent equation of matter waves and derive Schrödinger’s time Schrodinger’s time independent equation. (5) dependent and time 2) Derive Schrodingers Time Dependent equation for independent equations, matter waves. (5) 3) Derive Schrodingers Time Independent equation for matter waves. (5) Energy of a particle 1) Numerical on particle in a box. (5) enclosed in a rigid box 2) Explain Quantum Mechanical Tunneling (3) and related numerical problems, Quantum mechanical tunneling, Principles of quantum 1) What is quantum computing? What makes a computing: concept of quantum computer different from a regular Qubit computer? (5) 2) Write a short note on Qubit. (3) 6. Basics of Direct and Indirect Band 1) Write a short note on direct bandgap Semiconductor Gap Semiconductors, semiconductors. (5) Physics 2) Write a short note on direct bandgap semiconductors. (5) 3) Differentiate between direct band gap and indirect bandgap semiconductors. (5) Electrical Conductivity of 1) Numericals on conductivity, resistivity, mobility Semiconductors, Drift formulae. (5) Velocity, Mobility and 2) Derive microscopic form of Ohms law. (5) Conductivity in Conductors Fermi- Dirac distribution 1) Numerical on Fermi Dirac distribution function. (5) function, Position of Fermi Level in 1) Show that Fermi level is placed in the centre of the Intrinsic and Extrinsic energy band gap of intrinsic semiconductor. (5) Semiconductors. 2) Explain in detail the fermi level in case of intrinsic and extrinsic semiconductors. 3) Explain the position of Fermi level in N type semiconductor. 4) Explain the position of Fermi level in P type semiconductor. Note: students must refer to solved numericals shared separately.