Pressure Equation using Kinetic Theory of Gases (KTG) - Class 12 - Unit 15 Molecular Theory of Gases

In this Class 12 / Class 11 Physics lecture, we derive the fundamental Pressure Equation of an ideal gas using the Kinetic Theory of Gases (KTG) from Unit 15 (Molecular Theory of Gases). By analyzing the elastic collisions of gas molecules with container walls inside a cubic volume, we step-by-step derive the macroscopic gas pressure formula: P = 1/3 * ρ * v̄² (where P is pressure, ρ is density, and v̄² is mean square speed). We also demonstrate how to extract the Root Mean Square Velocity (v_rms = √(3P/ρ)). 📌 Download Free Class 12 Physics Notes: https://talhaphysicsacademy.blogspot.... ⏱️ TIMESTAMPS / CHAPTERS: 00:00 - Introduction & Physical Significance of Gas Pressure 01:39 - Setup & Geometry (Cubic Container, Area & Volume) 03:17 - Force & Impulse Definition (Newton's 2nd Law) 04:34 - Change in Momentum & Time Interval for 1 Molecule 08:54 - Single Molecule Force & Pressure along X-axis 10:56 - Total Pressure for N Molecules (Introducing Density ρ) 15:41 - Mean Square Velocity along X-axis (v_x²) 17:30 - Accounting for 3D Motion (Isotropic Velocity Distribution) 19:42 - Final Gas Pressure Derivation: P = 1/3 * ρ * v̄² 20:34 - Deriving Root Mean Square Speed (v_rms = √(3P/ρ)) 📚 RELATED LECTURES & PLAYLISTS: ▶️ Postulates of Kinetic Theory of Gases (KTG):    • Postulates of Kinetic Theory of Gases (KTG...   ▶️ Complete Class 12 Molecular Theory of Gases Playlist:    • XII Phy | Unit 15 Molecular Theory of Gases   💡 KEY FORMULAS DERIVED IN THIS VIDEO: 1. Single Molecule Force: F_x = (m * v_x²) / l 2. X-axis Pressure: P_x = ρ * v_x² 3. Total 3D Gas Pressure: P = (1/3) * ρ * v̄² 4. RMS Speed (Root Mean Square Velocity): v_rms = √(3P/ρ) 🔔 Subscribe to Talha's Physics Academy for step-by-step conceptual physics derivations, board exam preparation, and numerical problem guides! #KineticTheoryOfGases #KTG #Class12Physics #PhysicsDerivations #PressureEquation #MolecularTheoryOfGases #TalhasPhysicsAcademy #RMSVelocity #FScPhysics #PhysicsLectures