Practice question

Distance to 6kg: 6−2 = 4m. U = −Gm1r1−Gm2r2. U = −6.67×10−11(32+64). U = −6.67×10−11(1.5+1.5) = −2.001×10−10J/kg. As per NCERT, applying relevant law/formula with correct units and sign convention leads to -2.0 × 10⁻¹⁰ J/kg. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.