(SEM III) THEORY EXAMINATION 2022-23 ELECTROMAGNETIC FIELD THEORY

This question paper is structured to evaluate a student’s conceptual understanding, mathematical formulation skills, and problem-solving ability in Electromagnetic Field Theory. The paper covers electrostatics, magnetostatics, Maxwell’s equations, vector calculus, field relations, boundary conditions, wave propagation, and classical electromagnetic concepts that form the foundation of electrical, electronics, and communication engineering.

SECTION A – Short Answer Concepts (20 Marks)

This section contains 10 conceptual questions, each carrying 2 marks, designed to test the student's fundamental understanding of the EMFT principles. The questions include definitions, basic theorems, simple derivations, coordinate geometry, physical interpretations of electric/magnetic fields, and application-based reasoning. Topics include:

Conductance                                                            Magnetization and dipole moment

Gauss Divergence Theorem                                     Vector distances in coordinate systems

Electric flux density                                                  Lorentz force and field balance

Static magnetic field properties                              Maxwell’s time-varying equations

Current density relations                                        Poynting vector and energy flow

SECTION B – Analytical & Descriptive Questions (30 Marks)

Students must attempt any three questions, each carrying 10 marks.
This section evaluates the student's ability to derive, explain, and apply EMFT equations in real problems. Topics include:

Vector addition and velocity analysis (aircraft/wind problem)

Displacement current and its mathematical derivation

Infinite line current magnetic field formulation

Boundary conditions for magnetic fields

Electric field due to uniformly charged sphere (inside/outside/on surface)

These questions require clear mathematical steps, physical insight, and neat diagrammatic presentation.

SECTION C – Long Answer / Advanced Problem Solving (50 Marks)

This section contains five questions, each with two choices (attempt any one from each).
Each carries 10 marks and examines a deeper understanding of EMFT through derivations, proofs, and field equations.

Topics include:

Vector Calculus Theorems:

Stokes’ Theorem (statement + proof)
Gradient, divergence, curl in Cartesian, cylindrical, spherical coordinates

Electrostatics & Potential Theory:

Gauss’s Law and conditions for application                  Potential difference derivations

Maxwell’s Equations:

Static form of Maxwell’s equations (with proof)            Magnetic fields in coaxial transmission lines

Magnetics & Energy Concepts:

Magnetic torque vs dipole moment                              Magnetic energy derivation

Transmission Line Theory:

Smith Chart, uses, significance
Derivation of characteristic impedance and propagation constant
This section checks the student's ability to integrate theory with mathematical deduction.

OVERALL PURPOSE OF THE QUESTION PAPER

This exam is designed to:

Assess theoretical understanding of electric and magnetic fields.

Evaluate analytical and derivation skills.

Test application-based reasoning for practical electromagnetic problems.

Ensure students can link mathematical tools with electromagnetic physics.

Prepare learners for advanced subjects like Transmission Lines, Antennas, Waveguides, and RF Engineering.