A connecting rod has a mass of \(0.5 \mathrm{~kg}\). The radius of gyration through its centre of gravity is \(5 \mathrm{~cm}\) and its acceleration is \(2 \times 10^{4} \mathrm{rad} / \mathrm{s}^{2}\). The equivalent two-mass system for the connecting rod has a radius of gyration \(6 \mathrm{~cm}\). What is the correction couple of the equivalent system?

(a) \(11 \mathrm{Nm}\)

(b) \(9 \mathrm{Nm}\)

(c) \(6 \mathrm{Nm}\)

(d) \(2 \mathrm{Nm}\).