Collision Frequency, Mean free time (Relaxation time) & Mean Free Path | JEE Main Questions

#JEEMAIN2021 #KTG #THERMODYNAMICS #HEAT #JEEMAINSPECIAL #JEEMAINSPECIFIC #MEANFREEPATH #RELAXATIONTIME In the video expressions for Collision frequency, Mean free time or relaxation time and mean free path are derived. Questions asked in JEE main on theses concepts are also solved. Consider an ideal gas confined in an isolated closed chamber. As the gas undergoes an adiabatic expansion the average time of collision between molecules increases as Vq, where V is the volume of the gas. The value of q is (γ = Cp/Cv) (JEE Main 2015) An ideal gas is enclosed in a cylinder at a pressure of 2 atm and temperature 300 K. The mean time between two successive collisions is 6 X 10-8 sec. If the pressure is doubled and temperature is increased to 500 K the mean time between two successive collisions will be close to (JEE Main 2019, 12 January Evening) (a) 4 X 10-8 s (b) 3 X 10-6 s (c) 2 X 10-7 s (d) 0.5 X 10-8 s A 25 X 10-3 m3 volume cylinder is filled with 1 mole of O2 gas at room temperature 300 K. The molecular diameter of O2 and its root mean square speed are found to be 0.3 nm and 200m/s respectively. What is the average collision rate (per second) for O2 molecule? (JEE Main 2019, 10 April Morning ) (a) ~ 1010 (b) ~ 1012 (c) ~ 1011 (d) ~ 1013 Two gases Ar (40) and Xe (131) at same temperature have same number density. Their diameters are 0.07nm and 0.10nm respectively. Find the ratio of their Mean free time. (JEE Main 2020, 9th January Evening) In an adiabatic process volume is doubled then find the ratio of final relaxation time to initial relaxation time if γ = Cp/Cv (JEE Main 2020, 7 January Evening) Advanced problems Playlist    • Advanced Level Physics Problems For IIT JE...   JEE Main Revision Problems, JEE Main Specific Topics, JEE Main previous Year Questions Playlist    • JEE Main Special Topics theory Lectures, R...   Pathfinder Physics Solutions Playlist    • Pathfinder Physics Solutions   IRODOV Solutions Playlist    • Irodov Solutions   Toppling Roatational Mechanics Playlist    • Toppling | Rotational Mechanics | Theory &...   Instantaneous Axis of Rotation playlist    • Instantaneous Axis Of Rotation : Theory & ...   Center of Mass Frame Playlist    • Centre of Mass frame Theory & Examples for...   Physics Concept Videos for IIT JEE Advanced and Main, NEET    • Physics Concept Videos useful for IIT JEE   Theory Videos GEOMETRICAL OPTICS    • Geometrical Optics : Reflection From Plane...      • Geometrical Optics : Spherical Mirror : Th...      • Geometrical Optics : Refraction From Plane...      • Geometrical Optics : Refraction by Spheric...      • Geometrical Optics : Prism, Dispersion & A...   ELECTROSTATICS    • Electrostatics : Coulomb's law, Electric F...      • Electric Flux & Gauss Law : Theory Lecture...   GRAVITATION    • Gravitation : Theory Lectures for IIT JEE ...   CAPACITORS    • Capacitors : Theory Lectures for IIT JEE P...   MAGNETIC FORCE    • Magnetic Force : Theory Lectures for IIT J...   MAGNETIC EFFECTS OF CURRENT    • Magnetic Effects Of Current : Theory Lectu...