A disc of mass m kg is attached to a spring of stiffness k N/m as shown in the figure. The disc rolls without slipping on a horizontal surface. The natural frequency of vibration of the system (Hz) is
1
\(\sqrt{\frac{2k}{3m}}\)
2
\(\sqrt{\frac{k}{m}}\)
3
\(\frac{1}{2\pi}\sqrt{\frac{2k}{3m}}\)
4
\(2\pi\sqrt{\frac{2k}{3m}}\)