A string of length $1\mathrm{ }\mathrm{m}$ and mass $5\mathrm{ }\mathrm{g}$ is fixed at both ends. The tension in the string is $8.0\mathrm{ }\mathrm{N}$. The string is set into vibration using an external vibrator of frequency $100\mathrm{ }\mathrm{Hz}$. The separation between successive nodes on the string is close to