Practice question

E = −GMEm2r. r = 5RE = 3.2×107m. E = −6.67×10−11×6×1024×4002×3.2×107. E = −1.601×10176.4×107≈−2.5×109J. As per NCERT, applying relevant law/formula with correct units and sign convention leads to -2.5 × 10⁹ J. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.