(SEM I) THEORY EXAMINATION 2023-24 ENGINEERING PHYSICS

This document contains the B.Tech First Semester (2023–24) theory examination paper for the subject Engineering Physics (BAS101).
The paper is designed to assess students’ understanding of modern physics, optics, electromagnetic theory, quantum mechanics, nanomaterials, lasers, superconductivity, and fiber optics.

It is divided into three major sections (A, B, and C), each focusing on different difficulty levels and cognitive skills—from basic recall to analytical derivations.

SECTION A – Short Answer Questions (Fundamental Concepts)

7 questions × 2 marks = 14

This section tests concepts, definitions, and fundamental principles from various areas of physics.

Topics covered include:

1. Modern Physics & Radiation

Plank’s law and quantum postulates

Metastable states in lasers

2. Electromagnetic Theory

Physical significance of Poynting vector

Displacement current (related to Maxwell's equations)

3. Wave Optics

Effect of slit width smaller than wavelength (diffraction behavior)

4. Superconductivity

Vortex state in Type-II superconductors

5. Optical Fiber

Scattering loss and its causes

6. Nanoscience

Quantum confinement effect in nanomaterials

This section evaluates students’ K1–K2 level knowledge such as understanding, conceptual clarity, and scientific explanation.

SECTION B – Numerical & Application-Based Questions

Attempt any 3 × 7 marks each = 21

This section contains numerically intensive and application-oriented questions from quantum physics, EM theory, optics, and fiber optics.

Topics include:

1. Compton Scattering

Calculating Compton wavelength shift

Determining recoil electron’s kinetic energy

2. EM Wave Intensities

Calculating electric and magnetic field amplitude at a distance from a radiating source

3. Newton’s Rings

Using diameter of dark ring to compute radius of curvature and film thickness

4. Fraunhofer Diffraction (Single Slit)

Finding distance between first dark & next bright fringe

5. Optical Fiber Parameters

Calculating V-number (normalized frequency)

Determining number of guided modes

This section tests K2–K3 levels of understanding, requiring calculation, numerical substitution, and interpretation of physical formulas.

 SECTION C – Analytical & Derivation-Based Long Questions

One question from each: Q3, Q4, Q5, Q6, Q7 × 7 marks

This section measures higher-order thinking involving derivations, diagrams, and in-depth explanations.

Q3 – Wave Mechanics & Quantum Physics

(a)

Difference between phase velocity & group velocity; derive their relation

(b)

Quantum particle in a 1D box: energy eigenvalues and wavefunctions

Q4 – Electromagnetic Theory

(a)

Maxwell’s fourth equation and concept of displacement current (AC vs DC capacitor charging)

(b)

Derivation of Poynting theorem and interpretation of energy flow in EM fields

Q5 – Wave Optics

(a)

Interference in parallel thin films, maxima/minima conditions, complementary nature of reflection & transmission fringes

(b)

Fraunhofer diffraction from a single slit and intensity ratios of successive maxima

Q6 – Fiber Optics & Lasers

(a)

Acceptance angle, acceptance cone, derivation using numerical aperture

(b)

Construction & working of He–Ne laser; comparison with Ruby laser (advantages in stability, coherence, beam quality)

Q7 – Superconductivity

(a)

Difference between Type 1 and Type 2 superconductors; why Type 2 is preferred (high critical field, practical applications)

(b)

Purpose of Na (in context—likely incomplete in given text; generally related to electromagnetism or semiconductors)

Summary of Skills Tested

The paper evaluates:

Understanding of physical concepts

Mathematical and numerical application

Derivation and analytical reasoning

Diagrammatic explanation

Ability to integrate theoretical knowledge with real engineering systems

Covered domains:

Quantum mechanics

Optics (interference, diffraction)

Electromagnetic waves & Maxwell equations

Lasers & optical fibers

Superconductivity

Modern physics essentials