Practice question

ΔE = −GMEm(1r2−1r1). r1 = 3RE = 1.92×107m, r2 = 6RE = 3.84×107m. ΔE = −6.67×10−11×6×1024×300(13.84×107−11.92×107). ΔE = −1.201×1017(−2.604×10−8)≈3.13×109J. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 3.1 × 10⁹ J. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.