21 October
Complete bilingual TNPSC notes on Gravitation — Newton’s Universal Law of Gravitation, G vs g, variation of g, escape velocity (11.2 km/s), orbital velocity, Kepler’s three laws and geostationary satellites (35,786 km), with 15 key points, detailed notes in English and Tamil, 5 practice MCQs, memory tips and previous year questions for TNPSC Group 1, 2, 2A, 4 and VAO.