17159. The essential condition of placing the two masses, so that the system becomes dynamically equivalent, is (where l1 and l2 = Distance of two masses from the centre of gravity of the body, and kG = Radius of gyration of the body) September 13, 2025 by Admin l1 = kG l2 = kG l1l2 = kG l1l2 = kG2 ✅ The correct answer is option D.