Chapter 1: Physical World – Quick Revision Notes 1. Physics & Its Scope Study of nature and its laws. Divided into Classical Physics (Mechanics, Thermodynamics, Electromagnetism) and Modern Physics (Quantum Mechanics, Relativity, Nuclear Physics). 2. Fundamental Forces of Nature 1. Gravitational Force – Weakest but acts over infinite distance (e.g., Earth’s gravity). 2. Electromagnetic Force – Acts between charged particles (e.g., electricity, magnetism). 3. Strong Nuclear Force – Strongest, holds nucleus together, short-range. 4. Weak Nuclear Force – Responsible for radioactive decay. 3. Nature of Physical Laws Universal, consistent, and verified through experiments. Based on fundamental principles like Newton’s Laws, Conservation Laws (Energy, Momentum, Charge). 4. Physics & Technology Physics leads to technological advancements: Electricity → Electrical appliances Lasers → Medical and communication fields Nuclear Physics → Energy generation 5. Contributions of Scientists Newton – Laws of Motion, Gravitation Einstein – Relativity, Photoelectric Effect Maxwell – Electromagnetism C.V. Raman – Raman Effect S. Chandrasekhar – Chandrasekhar Limit (Astrophysics) 6. Importance of Physics Helps understand the universe (e.g., planetary motion, atomic structure). Basis for engineering, medical science, and space exploration. Final Tip for Exams: Focus on concepts rather than memorization. Understand the laws, principles, and real-life applications. Revise scientists and their contributions for objective questions. More Notes - https://whatsapp.com/channel/0029Va9492L3QxRv5MtNFF0Y/151