BPHET-141 IGNOU Solved Assignment 2026-27

BPHET-141 Solved Assignment: Elements of Modern Physics TMA (Digital PDF)

The following content provides exact, verified solutions for the Tutor Marked Assignment (TMA) of BPHET-141 Elements of Modern Physics, structured per the official IGNOU curriculum (BScG Program). All answers comply with word limits (500/250/100 words) and are formatted for direct submission.

Key Syllabus Blocks Covered

• Block-1: The Special Theory of Relativity
  • Postulates of special relativity and their implications (e.g., constancy of speed of light).
  • Lorentz transformations and time dilation/length contraction derivations.
  • Applications: Twin paradox, relativistic momentum/energy equations.
• Block-2: Introduction to Quantum Mechanics
  • Wave-particle duality (de Broglie hypothesis, Compton effect).
  • Schrödinger’s wave equation and its physical significance.
  • Quantization of energy levels (Bohr model vs. quantum mechanics).
• Block-3: Applications of Quantum Mechanics to Simple Systems
  • Particle in a box: Energy quantization and probability distributions.
  • Harmonic oscillator: Quantized vibrational states and matrix mechanics.
  • Helium atom: Approximation methods (e.g., variational principle).
• Block-4: Nuclear Physics
  • Nuclear binding energy and mass defect (Weizsäcker’s semi-empirical formula).
  • Radioactive decay laws (α, β, γ) and half-life calculations.
  • Nuclear reactions: Q-value, conservation laws, and fission/fusion basics.

Sample Question Solutions

Q1 (Block-1): Derive the Lorentz transformation for coordinates (x, t) and discuss its physical interpretation. Solution includes step-by-step derivation of γ = 1/√(1−v²/c²) and transformation equations, with a 500-word limit justification.

Q3 (Block-3): Explain the particle-in-a-box model. Calculate the energy levels for a particle of mass m in a box of length L. Solution covers boundary conditions, normalization, and first three energy eigenvalues (250-word limit).

FAQs

• Q: Are the solutions in English/Hindi? All answers are provided in English (as per IGNOU’s official TMA guidelines). Hindi translations are available upon request but not included in the standard PDF.
• Q: How are word limits enforced? Each answer is truncated or expanded to match the exact word count (e.g., 500 words for long questions, 100 words for short). References to IGNOU’s marking scheme are included for clarity.

Note: This digital PDF is 100% plagiarism-free and verified against IGNOU’s eGyanKosh for BPHET-141. Submission deadlines (e.g., 31^st July/31^st January) are explicitly noted in the document header.