A thin disk with a mass of \(5 \mathrm{~kg}\) and a radius of \(10 \mathrm{~cm}\) is connected to a torsional damper of coefficient \(4.1 \mathrm{~N} \cdot \mathrm{s} \cdot \mathrm{m} / \mathrm{rad}\) and a solid circular shaft with a radius of \(10 \mathrm{~mm}\), length \(40 \mathrm{~cm}\), and shear modulus \(80 \times 10^{9} \mathrm{~N} / \mathrm{m}^{2}\). The disk is subject to a harmonic moment of magnitude \(250 \mathrm{~N} \cdot \mathrm{m}\) and frequency \(600 \mathrm{~Hz}\). What is the amplitude of steady-state torsional oscillations?