A small bob tied at one end of a thin string of length 1 m is describing a vertical circle so that the maximum and minimum tension in the string are in the ratio $5: 1$. The velocity of the bob at the height position is $\_\_\_\_$ $\mathrm{m} / \mathrm{s}$.
$\left(\right.$ Take $\left.\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2\right)$