## Essential University Physics: Volume 1 (3rd Edition)

Using the equation that equates omega to the spring constant and the mass and using the equation $\omega= 2\pi f$, we find: $k = 4\pi^2f^2m=4\pi^2(4\times10^{13})^2(2.66\times10^{-26})=\fbox{1680 N/m}$