Thermodynamics Lecture 9 |Adiabatic and isothermal work done | PV Graph| JEE ADVANCED+MAINS| DPP
Thermodynamics Lecture 9 | Isothermal & Adiabatic Process – PV Graphs & Work Done (JEE Mains & Advanced) In this Thermodynamics Lecture 9, we take a deep and concept-oriented journey into two of the most important thermodynamic processes: Isothermal Process and Adiabatic Process. This lecture is specially designed for JEE Mains and JEE Advanced aspirants, while also being highly useful for Class 11, Class 12, NEET, and even strong Class 10 fundamentals. The lecture starts completely from the basic concepts and gradually moves towards advanced-level understanding, ensuring that every student — whether beginner or advanced — can follow smoothly. Special emphasis is given to PV diagrams, comparison between processes, and calculation of work done using mathematical derivations. 📘 What You Will Learn in This Lecture: 🔹 Isothermal Process (T = constant) Physical meaning of isothermal process Equation: PV = constant Derivation of work done in isothermal process Graphical interpretation using PV graph Area under PV curve and its physical significance Reversible isothermal expansion & compression Application in JEE Mains & Advanced problems 🔹 Adiabatic Process (Q = 0) Concept of adiabatic process Equation: PVᵞ = constant Derivation of work done in adiabatic process Why temperature changes in adiabatic process Comparison with isothermal process Steeper nature of adiabatic PV curve Real-life examples and exam relevance 🔹 Advanced PV Graph Analysis Comparison of Isothermal vs Adiabatic PV curves Slope analysis at the same point Identification of processes from PV graph Area comparison and work done relation Multiple process graphs in one diagram (Advanced level) 🎯 Why This Lecture Is Important? ✔ Frequently asked in JEE Mains & Advanced ✔ Core concept for Thermodynamics numericals ✔ Builds strong fundamentals for Heat Engines & Carnot Cycle ✔ Highly useful for NEET Physics ✔ Strengthens Class 11 Thermodynamics base 📄 DPP: PYQ-Based Practice Questions (JEE Level) Q1. An ideal gas undergoes isothermal expansion from (P₁, V₁) to (P₂, V₂). Derive the expression for work done and represent it on PV diagram. Q2. For the same initial and final volumes, compare the work done in isothermal and adiabatic processes. Justify using PV graph. Q3. A gas expands adiabatically such that its volume becomes double. Find the relation between initial and final temperature. Q4. Two curves on PV diagram represent isothermal and adiabatic processes passing through the same point. Which curve is steeper and why? Q5. An ideal gas undergoes reversible isothermal expansion at temperature T. Show that internal energy remains constant. Q6. Calculate the work done during adiabatic expansion of an ideal gas in terms of initial and final pressures and volumes. Q7. From a given PV graph, identify whether the process is isothermal or adiabatic with proper reasoning. Q8. Prove that work done in isothermal expansion is always greater than adiabatic expansion between same volumes. Q9. An ideal gas undergoes cyclic process involving isothermal and adiabatic steps. Identify the process from PV graph. Q10. A monoatomic gas expands adiabatically. If pressure becomes 1/16th, find the change in volume. 🚀 Who Should Watch This Lecture? ✔ JEE Mains 2025 / 2026 Aspirants ✔ JEE Advanced Students ✔ NEET Physics Students ✔ Class 11 & 12 Board Students ✔ Students who want strong conceptual clarity 📌 Hashtags (SEO Optimized) #Thermodynamics #IsothermalProcess #AdiabaticProcess #PVGraph #WorkDoneInThermodynamics #JEEPhysics #JEEMains #JEEAdvanced #NEETPhysics #Class11Physics #Class12Physics #Class10Physics #ThermodynamicsForJEE #PhysicsNumericals #PhysicsConcepts #PYQPhysics #DPPPhysics #IITJEE #HeatAndThermodynamics
