A satellite orbits a planet at 3×107m from its center with a period of 6 hours. What is the planet’s mass? (G\=6.67×10−1
M = 4π2r3GT2. T = 6×3600 = 21600s, T2 = 4.6656×108s2. r3 = (3×107)3 = 2.7×1022m3. M = 4×(3.14)2×2.7×10226.67×10−11×4.6656×108. M = 1.065×10243.112×10−2≈3.42×1025kg. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 3.4 × 10²⁵ kg. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.
Ref: Halliday & Resnick, Fundamentals of Physics, 11th ed., Chapter 13: Gravitation.