About this previous year paper
This is a 3-hour Physics/Applied Science examination of 100 marks. The paper is divided into three sections – A, B, and C, and students must answer questions from all sections as instructed. Standard values may be taken wherever needed. The paper focuses on topics such as crystal physics, dielectric properties, electromagnetic waves, magnetism, superconductivity, semiconductors, and nanomaterials.
Section – A (20 Marks)
Section A contains 10 short questions, each of 2 marks. Students must attempt all parts. These questions test the basic definitions and fundamental concepts of the subject. Topics include primitive cells, atomic radius in cubic structures, internal electric fields in dielectrics, magnetic materials used in transformers, displacement current, relation between electric and magnetic fields in EM waves, the Fermi level in intrinsic semiconductors, transition temperature of superconductors, critical magnetic field, and types of single-walled carbon nanotubes.
This section focuses on quick recall, conceptual understanding, and short explanations.
Section – B (50 Marks)
Section B contains eight descriptive/numerical questions, out of which any five must be answered. These questions are designed to test the student's ability to explain concepts, solve derivations, and perform calculations. Questions cover:
crystal structure, lattice and Bravais lattice
lattice planes and interplanar spacing in cubic structures
polarization of materials and its mechanisms
susceptibility of diamagnetic materials
derivation of EM wave equation from Maxwell’s equations
Poynting vector and radiation calculations
temperature dependence of critical field in superconductors
carbon nanotubes, their properties, and applications
This section checks analytical skills, derivations, mathematical steps, and detailed understanding.
Section – C (30 Marks)
Section C contains three long-answer questions, out of which any two must be attempted. These questions require in-depth explanation, derivations, and detailed reasoning. Topics include:
Bragg’s law and the working of Bragg’s spectrometer for studying crystal structure
dielectric constant, Clausius–Mossotti equation, behavior of dielectrics in AC fields, and relaxation time
drift velocity, mobility, intrinsic semiconductor conductivity, and numerical calculation of donor concentration in n-type materials
This section tests higher-level understanding, ability to write long theoretical answers, and perform multi-step numerical calculations.
Overall Summary
This question paper assesses a student’s knowledge of solid state physics, dielectric behavior, Maxwell’s equations, semiconductors, superconductors, and nanotechnology. Section A checks basic concepts, Section B focuses on explanations and numericals, while Section C evaluates deep understanding and derivation skills.